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A great deal is made of Arsenal's over-reliance on Olivier Giroud and their lack of a back-up striker of significant quality, so it will have been pleasing for Arsene Wenger and doubly so for the club's England fans to have seen Joel Campbell tear Uruguay apart in Costa Rica's opening game at the World Cup. He scored a wonderful goal for Olympiakos in the Champions League win over Manchester United earlier this season, but it was still a vast surprise to see him inspire lowly Costa Rica to historical victory.
Campbell was the star of the show as the Central Americans came from behind to beat their South American counterparts. Uruguay were unquestionably favourites ahead of the game and it took a remarkable performance from Campbell to turn the game on its head. Playing through the middle in Costa Rica's 5-4-1, Campbell was the man of the match with a rating of 9.21, having scored the equaliser and set up his side's third with a scything through ball. The Arsenal man was always a threat, dropping deep to collect possession - and being fouled a tournament-high seven times - then also looking for balls in behind, thus being caught offside twice. He had four shots and also completed seven successful dribbles, all of which will give Costa Rica confidence that they can provide another upset against Italy or England.
For Arsenal, meanwhile, if Campbell can perform to these standards and continue to develop too, he could even be the answer to their striker problems next season, though Gunners fans may be hoping he doesn't impress their manager so much that he opts not to dip into his war chest.
Netherlands' resounding 5-1 victory over Spain was undoubtedly the biggest shock of the opening round of fixtures, and while Arjen Robben and Robin van Persie took the plaudits, it was left wing-back Daley Blind who really stood out. Doubters had questioned whether Netherlands had the quality in wide positions to switch to a 3-5-2 formation and accommodate Robben and Van Persie in a two up front.
But Blind, who played much of the season in central midfield for Ajax, provided two outstanding assists for the Netherlands' first two goals, each chipped through balls that left one of the Oranje's forwards clean through on goal. No player has played more through balls at the World Cup so far than Blind (2), and it speaks volumes about this youngster's ability and vision that the two players who can match him in this statistic are Andrea Pirlo and David Silva.
Antonio Candreva is far from an unknown entity in Italy, but when England fans saw Italy's line-up, many will have thought this 27-year-old was far from as good as the rest of Italy's star-studded midfield. Candreva may lack in technical ability compared to the likes of Pirlo and Daniele De Rossi, but what he lacks in that regard he makes up for in sheer work rate. He made clever runs off the right flank to at times become a second striker off Mario Balotelli, and had the joint-most shots in the clash (4), including one which rattled Joe Hart's post. When he did remain out wide, he was lethal, setting up Mario Balotelli's winner with his only key pass of the game - an inch-perfect cross to the back post for the striker to nod home.
The USA picked up an unexpected but highly deserved 2-1 win over Ghana in their opening game, with a performance that will have given the squad great confidence for the rest of the tournament. Geoff Cameron, hardly the most celebrated of Stoke's players, was a rock at the back, blocking two shots, making one last-man tackle and also winning three aerial duels on his way to a WhoScored rating of 7.60. His incredible total of 15 clearances was more than England, France, Spain, Netherlands or Chile made as a whole in their opening games.
On the final day of the opening round of World Cup 2014 fixtures, Belgium overcame an early scare to beat Algeria 2-1, and it was an unlikely substitute who inspired their comeback. Marouane Fellaini was introduced with 25 minutes to go and within five minutes he had levelled the game, scoring a wonderfully flicked header that cannoned in off the underside of the bar. He has spent most of the season being criticised for below-par displays for United after his £27m move from Everton, but he turned Belgium's opener on its head yesterday. His rating of 7.88 was the second highest by a substitute at the 2014 World Cup so far (behind USA's John Anthony Brooks' 8.05) and the mop-haired midfielder will be hoping he has now turned a corner.
Ali Tweedale - follow him on Twitter.
All statistics courtesy of WhoScored.com, where you can find yet more stats, including live in-game data and unique player and team ratings.