FULL TIME: Argentina (Higuain 8) 1-0 Belgium. Argentina join Brazil and Germany in the World Cup semis.
95 - Witsel thumps a long-range effort over! Surely that's the last chance.
94 - Courtois does brilliantly to foil Messi in a one-on-one situation! Messi should have buried that.
93 - Time running for the Belgians as Vertonghen tries in vain to find the big men Lukaku and Fellaini with a cross into the box.
90 - There will be five minutes of added time.
85 - De Bruyne has a shot deflected just wide for a corner. That could have gone anywhere.
83 - Zabaleta's cross from the right is just too high for the 5ft 7inch Palacio, who took up an excellent position in the box.
81 - Argentina sub: Gago replaces Higuain.
75 - Argentina booking: Biglia is cautioned for a challenge on Vertonghen. Belgium sub: Chadli replaces Hazard.
74 - Witsel has a speculative effort charged down.
73 - Fellaini is harshly penalised when tussling with Garay. There have been a lot more free-kicks this half.
71 - Argentina sub: Palacio replaces Lavezzi.
68 - Belgium booking: Alderweireld is cautioned for a studs-up challenge on Biglia, and is suspended for the next game should his country progress.
65 - Garay slides to cut out a right-wing cross by De Bruyne and inadvertently directs the ball towards his own goal, but his goalkeeper Romero is alert and collects at his near post.
61 - Fellaini rises about Basanta to power a header narrowly over off a left-wing cross by Vertonghen!
60 - Belgium double sub: Mertens replaces Mirallas, Lukaku replaces Origi.
59 - Kompany slides in to arrest a strong run from Lavezzi. At second look that looked a foul, but the Belgian skipper got away with it.
55 - Argentina hit the woodwork! Higuain clips the cross bar with a powerful strike after running all of 60 yards!
53 - Lavezzi, who has had a quiet game, sends in an inviting ball across the face of goal but there is no teammate on hand to capitalise. Belgium booking: Hazard is cautioned for a poor challenge on Biglia. He has no complaints.
52 - Higuain has a shot deflected wide of the post by Bayern Munich defender Van Buyten.
51 - Zabaleta blocks a cross by Vertonghen, who was put into space down the left by Hazard.
48 - Higuain twists and turns to draw a foul by the imposing Kompany. Messi's resultant delivery into the box is poor and the ball goes out for a goalkick.
HALF-TIME: Argentina (Higuain 8) 1-0 Belgium.
45 - There will be two minutes of added time.
42 - Mirallas sends a diving header a foot wide of the post off a telling left-wing cross by Tottenham utility player Vertonghen! That was close.
40 - Messi drills his set-piece high and wide.
38 - Messi goes down on the edge of the area under a challenge from Fellaini and earns a free-kick. Belgium are not impressed with the ref's decision.
37 - Argentina knock it around in relative comfort Belgium are briefly down to ten men as De Bruyne receives some treatment for a slight complaint.
33 - Argentina sub: Perez comes on for the injured Di Maria, who has taken a knock to the right knee.
32 - Kompany heads clear a left-wing cross intended for Higuain. The Manchester City skipper had to win that.
28 - Kompany blocks a shot from Di Maria, who was put into space by Messi's superb defence-splitting pass.
27 - De Bruyne has a crack on goal but Romero is equal to the task.
26 - Witsel does well to track Messi's run down the right before gaining possession with the help of a teammate.
25 - Hazard is robbed of the ball by Biglia, the Chelsea playmaker has not had the best of tournaments to date.
23 - Di Maria tries a deft flick on the edge of the area in search of Higuain, but his radar is a touch off. Nice idea though from the Real Madrid ace, who of course scored a late winner against the Swiss in the last-16.
20 - Messi is penalised for a shove on Witsel, moments before Hazard goes tumbling on the edge of the area. Ref Rizzoli is having none of it though, much to the visible delight of Mascherano.
17 - Vertonghen skips past Di Maria down the left before whipping in a decent cross, which is dealt with by Garay.
15 - Fellaini fells Messi in midfield after being given the run around by the little magician.
13 - De Bruyne slices a left-footed effort wide of the target after pushing forward with intent.
8 - ARGENTINA GOAL! Higuain scores his first goal of the tournament with a first-time volley just inside the area! Stylish finish that after the ball sat up kindly for him after Di Maria's pass ricocheted off a Belgium defender! Argentina 1-0 Belgium.
6 - Mascherano signals to the referee Nicola Rizzoli that he wants Mirallas to be cautioned for a dive, but the official keeps his cards in his pocket.
5 - Di Maria steps in energetically off the right flank before having a left-footed shot blocked on the edge of the area.
3 - Messi releases Lavezzi with a fine ball down the left but the latter's weak cross is comfortably dealt with by Kompany.
2 - Decent start by the Europeans, with Witsel showing good strength to shrug off Mascherano in a midfield tussle. Bit of niggle early on.
1 - Belgium get us underway!
Both countries have won all four of their games at the tournament, with Lionel Messi's side edging Switzerland 1-0 in the last-16, while Belgium beat the United States 2-1 in their previous outing.
Argentina coach Alejandro Sabella has made three changes to his starting XI, bringing in Manchester City centre-back Martin Demichelis, fellow defender Jose Basenta and midfielder Lucas Biglia for Federico Fernandez, suspended left-back Marcos Rojo and Fernando Gago.
Belgium boss Marc Wilmotts has effected one change to his unit, as Everton forward Kevin Mirallas gets his second start of the competition ahead of Napoli attacker Dries Mertens.
The teams have been announced:
Argentina: Romero; Zabaleta, Demichelis, Garay, Basanta; Biglia, Mascherano, Di Maria; Lavezzi, Messi, Higuain.
Belgium: Courtois, Alderweireld, van Buyten, Kompany, Vertonghen, Witsel, Fellaini, De Bruyne, Mirallas, Hazard, Origi.