22:05 CET: It was a mostly cagey game tonight that took a long time to get going. Looking at the stats below, you can see that there weren't many chances for either side but Argentina had that little bit of extra quality needed.
That's what a player like Messi can give you, and Fernandez's strike was also excellent.
The win means the crisis is averted for Argentina but they still have plenty to prove. Mexico, meanwhile, aren't out of the tournament mathematically but they will need to beat Saudi Arabia in what could be a winner-takes-all match.
Read Juan Pablo Aravena's full match report here.
Second Half
21:57 CET: That is full-time here and Argentina have done it. It wasn't always pretty but two great goals have handed them the three points they desperately needed.
21:52 CET: There will be six added minutes here. It seems far too late for Mexico to come back now.
21:48 CET: GOAL! ARGENTINA! And that one was a real beauty. Enzo Fernandez beats his man at the edge of the box, after receiving the ball from a short corner routine, and bends it into the far corner. Lovely controlled finish from the substitute and, surely, that's the game.
21:41 CET: Only 10 minutes to go and looking at our live Opta win probability, Argentina should take this one home but it's not over yet.
21:36 CET: Just 15 minutes to go and that Messi strike is what separates these two. It's been just two shots on target versus one. Can Mexico shake things up with an equaliser?
21:34 CET: And another change for Mexico. Lozano is replaced by Alvarado. Mexico need to try and get back into this game although losing tonight would not put them out necessarily.
21:29 CET: A few substitutions have occurred. Jimenez and Antuna are on for Mexico in place of Vega and Alvarez. Palacios and Romero are on for Argentina in place of Mac Allister and Di Maria.
21:27 CET: Yellow card for Hector Herrera (Mexico).
21:25 CET: GOAAAALLLL! MESSI! Finally a breakthrough! A great goal too. The ball was squared to the little maestro outside the box while he was in loads of space. He picked his spot and directed it low into the bottom right corner and out of reach of Ochoa in the Mexican goal.
21:24 CET: Double change for Argentina as they look for something different. Montiel and L. Martinez are off. Alvarez and Molina are on.
21:20 CET: The first hour has been really tight as we've mentioned. Argentina have dominated possession but it's mostly been passive. Just one shot on target for each side so far.
21:18 CET: Just approaching the hour mark here and Argentina are making a change. Guido Rodriguez departs the field of play to be replaced by Enzo Fernandez. They will be hoping that Fernandez can open something up because it's a bit of a stalemate here and that does not suit Argentina at all.
21:14 CET: Erick Gutierrez has gone into the book for Mexico for an earlier foul.
21:12 CET: Messi makes his first mark on the match with a mazy run into danger before being fouled on the edge of the area. He lines up the free kick but it's a poor effort - it flies well over.
21:06 CET: Argentina get the second period of play underway.
20:55 CET: As you can see in the stats below, there hasn't been too much action in this match. Maybe things will open up in the second half.
First Half
20:50 CET: Vega fires a shot high and wide. And that's halftime. Hmm, well not the exciting half of football we had all hoped for. There hasn't been much to cheer - Messi has been mostly invisible and there have been only a couple of shots by each team - and yet the fans of both sides just keep cheering. It does feel like a goal could burst this match into action. Stay tuned for the first-half stats and the second half in this crucial match in Group C.
20:46 CET: Five minutes have been added on to this half.
20:45 CET: It's a good effort from the resulting free kick by Vega. He manages to get it up and over the wall but Emiliano Martinez saves it well.
20:43 CET: Gonzalo Montiel picks up the game's second yellow card, Argentina's first, for a late tackle.
20:41 CET: A shot for Argentina finally as Lautaro Martinez heads over the Mexican bar. Not too threatening, really. And Mexico are making a change now, it seems like an injury to Andres Guardado. He is replaced by Erick Gutierrez.
20:34 CET: Another zesty challenge by Alexis Vega - expect him to get booked soon.
20:31 CET: Still zero shots on target as we reach the half-hour mark here.
20:28 CET: Barely a blip on our Momentum graphic as you can see below. Not much action in the first 25 minutes of play but, as you can also see, it has swung between the two sides. It's an even contest so far.
20:23 CET: Nestor Araujo (Mexico) picks up the first yellow card of the match for a pretty bad sliding challenge. That is what you call an 'orange card' - almost a red.
20:20 CET: This is a critical match for both teams as neither has yet won in the group stage. You can really feel that tension, too, which is only aided by the intense atmosphere in the stands. It feels like a classic tight World Cup match for all those reasons. Don't expect a lot of goals here tonight if it stays this way but one goal could open it all up!
20:17 CET: The first quarter hour has been really cagey and tense. Argentina has dominated the ball, as expected, but haven't crafted any chances. The only shot of the game has come from that Mexico free kick.
20:10 CET: First big chance as a Mexican free kick is whipped into the box and eludes everyone but fizzes through the danger zone.
20:06 CET: Alexis Vega of Mexico elbows Montiel as he looks to break on a counterattack. It could have been a yellow card but the referee says just a foul. This could be a fiery match if that challenge is a sign of things to come. The stadium is bouncing so it wouldn't be a surprise to see that energy seep down onto the pitch.
20:00 CET: Mexico kick off and immediately launch it forward and out of play.
19:56 CET: The referee for this match will be D. Orsato of Italy. Argentina are kitted out in their classic blue and white stripes, Mexico in their iconic tri-colour combination of green, red and white. It's really loud out there! Pure passion from the two sets of fans during the anthems.
19:54 CET: The teams emerge into a vibrant atmosphere and it promises to be a cracker at the Lusail Iconic Stadium. Reputations go out the window now, it's a matter of whether you can perform when it really counts.
Team News
Lionel Scaloni has made five changes to his Argentina side, hoping to reignite their pursuit of a third World Cup title.
Argentina bring Guido Rodriguez and Alexis Mac Allister into midfield and Marcos Acuna, Gonzalo Montiel and Lisandro Martinez into defence, but keep faith with their strike force of Lionel Messi, Angel Di Maria and Lautaro Martinez.
Mexico, who scraped a goalless draw with Poland in their opener, dropped forward Henry Martin and stuck with Hirving Lozano and Alexis Vega up front.
Tata Martino has brought in defenders Kevin Alvarez and Nestor Araujo along with midfielder Andres Guardado but again opted against starting forward Raul Jimenez.
Argentina: Emiliano Martinez, Gonzalo Montiel, Rodrigo De Paul, Marcos Acuna, Lionel Messi, Angel Di Maria, Guido Rodriguez, Nicolas Otamendi, Alexis Mac Allister, Lautaro Martinez, Lisandro Martinez
Mexico: Guillermo Ochoa, Nestor Araujo, Cesar Montes, Alexis Vega, Hector Moreno, Hector Herrera, Andres Guardado, Hirving Lozano, Jesus Gallardo, Luis Chavez, Kevin Alvarez
See how the teams shape up here.
Introduction
Argentina do not have to win this match to stay in the tournament but they certainly cannot lose to Mexico tonight. Their shock 2-1 loss to Saudi Arabia mounted pressure on the team and dented their chances of exiting the group. A win would get them straight back on track and confirm that the loss was merely a blip.
Make no bones about it, this is a side that came to Qatar targeting the trophy. They have been one of the in-form international teams in the world, having won Copa America this year and gone an incredible 36 matches unbeaten before the loss last week. They will be the heavy favourites in this match but will the pressure be too much?
Mexico, on the other hand, managed a creditable, if uneventful, 0-0 draw with Poland in their opener and they will be looking to spring a surprise tonight. They are in the advantageous position of being the underdog and that plays into their hands. Can they do what the Saudis did?
Stay tuned to find out with our live updates or use listen to our audio commentary here.
