Before a big game, within a locker room, there's a general sense of who the key player is for the upcoming game — the most important player on that day, the MiP. That guy isn't always the best player on the team; rather, he's the player with the biggest marginal influence — his performance could be the difference between sipping a glass of champagne after the game or chugging a warm beer at the local dive bar. Sometimes it's stated explicitly within the team, sometimes it isn't; it could be related to the tactics on the day, matching up with a specific opponent, or simply that the star player needs to make a big play. Either way, there's always a player that the team needs to have a big game.

Here is every team's MiP heading into the Audi 2019 MLS Cup Playoffs:

Atlanta United

Leandro Gonzalez Pirez

If we could be sure that Miles Robinson, who left USMNT camp with a strained hamstring, would be fit, he would be the answer here. With the way Atlanta United play now — open, end-to-end — you need someone to put out fires; Robinson has become the best firefighter in the league. If Robinson isn't available, LGP needs to take that role. The thing about LGP: He might be the most talented center back in the league. His combination of short passing, long passing, ability to read the game, tackling and athleticism might put him in a category of his own. Unfortunately, he's also become one of the most inconsistent center backs in the league. If Atlanta United want to win a second straight MLS Cup, they need LGP close to his best.

FC Dallas

Michael Barrios

It'll be road games throughout the playoffs for FCD. Zdenek Ondrasek has been the revelation of the fall in MLS, but he's probably not the right guy for a playoff game on the road. FCD's best two away performances of the last couple months have come when they used a quicker option up top. Look for Dallas to start Barrios at striker on Saturday. The Colombian played as the center forward in a counter-attacking setup when Dallas took a 0-0 draw in Seattle. You always know that Barrios will cause problems running behind and taking players on with the dribble; he's tallied 35 assists in the last three years. The frustrating part is that he could have more if he were tidier on the final ball.

DC United

Paul Arriola

Arriola, now a second striker/attacking midfielder for D.C., will have two main roles on Saturday. First, he will need to negate Toronto FC's Michael Bradley. Toronto flows through Bradley, and if you can cut off that artery, they struggle to find a rhythm. Second, Arriola will be the first to fly forward in transition. Toronto are extremely vulnerable when they give the ball away; they send both outside backs forward, and neither the center backs nor the defensive mids are great at covering the space. Wayne Rooney doesn't quite have the wheels to punish teams on the break anyway, so it'll be up to Arriola to hit the openings.

LA Galaxy

Diego Polenta

You could take this one in a few different directions — and, strangely or not, none of them point to Zlatan Ibrahimovic. Zlatan is a constant variable. If you put the ball near his body, he's going to do his thing. The important elements for the Galaxy are getting the ball to Zlatan in good spots (which, as JJ Devaney pointed out on the Caught Offside podcast, is with the star DP as the highest player, usually around the box, rather than as the playmaker) and defending in their own box. Jonathan dos Santos is the most important player for the first one, and Diego Polenta is the key guy for the second. JDS has become a pretty steady rock for the Galaxy and you know what you're going to get from him. Behind him... not so much. The Galaxy have given up 10 more goals than any other team from the Western Conference in the playoffs this year, including conceding eight goals in their last two games. If the Galaxy defenders play at even an average level in the back, they are one of the favorites in the playoffs.

LAFC

Jordan Harvey

We've seen a clear pattern with LAFC in the last two months: their opponents have dropped their lines deeper and tighter. Watching LAFC vs. anybody recently looks like watching Manchester City vs. Burnley. LAFC dominate the ball and the flow of the game; it's been a matter of creating high-probability chances. When opponents drop that deep, it's usually the outside backs who have the most space to attack. Harvey, on the left, has become the more attacking of the two outside backs (the winger on his side, Diego Rossi, likes to cut in, opening up the wide channel for the secondary movement; the winger on the right side, Brian Rodriguez, prefers to stay wide and dribble 1v1). The flip side of that, though, is that the playbook to beat LAFC involves playing behind the outside backs in transition. So Harvey needs to get forward to create chances but still be aware of the space behind him.

Minnesota United

Ike Opara

This one is simple. Opara vs. Zlatan. The frustrating part of playing the Galaxy is that nothing else really matters until those few seconds of the ball drifting toward Zlatan's head in the box. The Galaxy could play terribly and then they clip a ball into the Swede and he saves them. The Galaxy will probably play plenty of those balls, too, since the Loons are likely to sit in a tight defensive block and force the Galaxy wide. Thankfully for Minnesota, they have the player in the league most equipped to deal with those balls. Opara is a beast in the air; he's athletic, he understands how to use his body to own the space he wants, and he's not scared of anyone — he's one of the few players who will relish, rather than fear, the challenge of playing Zlatan.

New England Revolution

Gustavo Bou

Here's the thing about the Revs: It's impossible to predict how they are going to play. They have used five different formations since Bruce Arena has taken off and rotated their starters just as often. Arena hasn't established a clear preferred formation or starting lineup. It's either a huge advantage or a huge liability going into the playoffs, depending on your preferences. To Arena, I suspect it's an advantage. As such, though, it's tough to pinpoint a player that's particularly important to a certain matchup or part of the game. Best case scenario for the Revs is probably an ugly game in which neither team establishes a rhythm and it's left to a couple of big plays to decide the outcome. Most teams would dread that type of game against the high-powered Five Stripes. The Revs, though, are strangely suited to it. They have the high-end talent to match Atlanta, with Matt Turner, Carles Gil, and Gustavo Bou each capable of game-changing plays. Turner would be a suitable answer here, but it's ubiquitously true in any game that if one goalkeeper stands on his head that team will win. I'm going with the guy most likely to make a ridiculous play on the other end: Bou. 

New York City FC

Ronald Matarrita

Why Matarrita? Simply because he's the only one on the team who might have a stinker. It's tough to find any other maybe's with NYCFC right now. They have a counter-solution to every problem that could arise. Dome Torrent has built his dream scenario. So then we need to ask, "who might blow it?" It's a team of established pros, but Matarrita is the most likely candidate. He still has an errant pass or red card moment in him. It's not so much about the Costa Rican having a big game, but rather not having a bad one. 

New York Red Bulls

Cristian Casseres Jr.

The way that Red Bull beat Philly is by giving them a good old-fashion bruising. I understand why Chris Armas attempted to help the team evolve. If there's any situation that's ripe for the Red Bulls' Way, though, it's playing against the Union, a passing team, at Talen Energy Stadium. Philadelphia will try to play out of the back and through midfield and Red Bull will have a chance to harness their original tenets: pressure on the ball, win second balls and transition passes up the gut. It's tough to stick to those principles, however, without someone bossing the middle of the field. If Casseres Jr. can cover ground and win his duels, it frees everyone up around him to press earlier and commit more. If Casseres Jr. struggles, though, it could be easy sailing for the Union. 

Philadelphia Union

Kacper Przybylko

There are two key variables for the Union heading into the game with RBNY.

1. Can they compete at the Red Bulls' intensity level?
2. Will they finish their chances?

Przybylko could be the key to both of those. The striker is given the phrase, "lead the line," for a reason. He's the player in everyone's sightline on his team. He's also usually the first one to act. If he's energetic and animated, it can boost the rest of his team (think David Villa). If he's slow and languid, it can bring his team down.

Then there's just the simple math of the striker finishing chances. We've been saying it about the Union for three years. Przybylko seems to have been the answer, scoring 15 goals to finish tied for fifth in MLS this year. As RBNY fans know as well as anyone, though, it's one thing to score regular-season goals and it's another to finish in big moments in the playoffs. 

Portland Timbers

Sebastian Blanco

Remember this?

That's what the Timbers are at this point, right? The same thing they were at this stage last year... keep the game close and then win it with big moments from star players. They rode it to MLS Cup last year. There might not be anyone more capable of those moments than Blanco.

Real Salt Lake

Aaron Herrera

If Blanco is the key player for Portland, then that makes Herrera, the right back going head to head with Portland's left winger, the most important player for RSL. Portland will look to switch the ball quickly and isolate Blanco against the RSL defender. If Herrera can hold his own, it will both stifle Portland's main attacking threat and set up RSL on the break. 

Seattle Sounders

Nico Lodeiro

There's a strong case to be made that Lodeiro is the most valuable player in the league — that he means more to his team than any other player in MLS. It'll be as true as ever in the playoffs. Dallas will play on the counter at CenturyLink Field in the first round, same for RSL or Portland in the second round, and Seattle don't have Ozzie Alonso or Chad Marshall anymore to save them in defensive transitions. The Sounders will need to be more meticulous in how they use the ball with any giveaway potentially leading to the end of their season. The main character in that will, of course, be Lodeiro. The Uruguayan will need to find the balance between making safe, smart passes as the facilitator and also the killer balls as the playmaker. If he does too many of the first, Seattle could be toothless; if he attempts too many of the second, Seattle could get exposed in transition. 

Toronto FC

Michael Bradley

Yes, the answer to this is still Michael Bradley. The three players with the biggest swings in their performances this year: Francisco Calvo, Leandro Gonzalez Pirez and Michael Bradley. Is it mind-boggling that Bradley (the General!) is on that list? It absolutely is. Is it mind-boggling that Bradley, who started Tuesday's Canada game primarily for his senior presence and leadership, gave away the ball that led to Canada's game-winner? It absolutely is. But that's where we are at. Bradley can still be the best player on the field, as we saw in Toronto's 1-1 draw with LAFC last month, and he can also be a liability. Does it hurt me, a longtime Bradley fan, to say that? Yes, it does. But it feels like Bradley, more than anyone, would want it pointed out.