Here, Sports Mole takes an in-depth look at another incredible 90 minutes of World Cup action.
On target: 4
On target: 5
Was the result fair?
It is impossible to begrudge Costa Rica the victory today as they worked incredibly hard to stifle Italy and not allow their playmakers any room to manoeuvre. Most of the stats lie in Italy's favour, but the simple fact is that they did nowhere near enough with their 61% possession.
In terms of chances, Italy just about edged it with a couple of first-half openings for Mario Balotelli, but overall the Costa Rican defence was rarely seriously troubled. Apart from two stops in the first 10 minutes of the second half, Keylor Navas was a mere spectator for large periods after the break.
Costa Rica simply looked like they wanted it more than the Italians, who didn't inject any pace or urgency into their attacks throughout. They may feel that a draw would have been fair, but Costa Rica certainly didn't steal this victory, they earned it.
Very disappointing. Having set a new World Cup record for passing accuracy against England, the Italians were uncharacteristically sloppy in possession this afternoon, misplacing a number of passes and failing to get into any sort of rhythm when trying to build attacks.
The likes of Andrea Pirlo, Mario Balotelli and Daniele De Rossi were kept quiet for the vast majority of the game, and Italy didn't seem to have an answer for that. Their attacks were laboured and slow, while they looked susceptible to the pace of Joel Campbell at the other end of the pitch.
It was certainly a worse display than the one they put in against England, and their hopes of qualifying for the second round now hang in the balance. They face Uruguay in a winner-takes-all encounter on Tuesday, and if they play like they did today in that match then the South Americans would have to be heavy favourites.
Costa Rica's performance
Very impressive. Costa Rica worked incredibly hard off the ball all match, hounding the Italian players and pressing high up the field to limit the time and space given to the likes of Pirlo. They defended with a high line throughout, but Italy were unable to get behind them - thanks largely to the Azzurri attackers spending most of their time offside.
They defended very well as a team and also caused Italy a number of problems when going forward themselves. Clear chances were few and far between, but the pace of Campbell always looked like a promising outlet for them. They were unfortunate not to have a penalty shortly before they took the lead, with Campbell clearly being fouled in the area.
Every single player did their job very well this afternoon. Costa Rica were tipped by some to be the whipping boys of Group D, but on today's evidence they stand a very good chance of beating England and finishing the group stage with a maximum nine points. Having already beaten Uruguay and Italy - both deservedly - they may even be dreaming of a long World Cup run.
Sports Mole's man of the match
Junior Diaz: It was a superb performance from the Costa Rican left-back, who delivered a magnificent cross into the box for the only goal of the game. He was up and down the flank all afternoon and was as impressive defensively as he was in attack.
This one goes to Mario Balotelli for spurning a great chance to give Italy the lead when the match was still goalless. Pirlo, free from tight marking for once, played a wonderful pass in behind the defence for the striker to run on to, but he lifted his effort over the keeper and some way wide when he should have scored.
It was a mixed bag from referee Enrique Osses, who allowed play to flow quite well but also made some wrong decisions. The most glaring error was the failure to award Costa Rica a penalty at the end of the first half when Campbell was clearly brought down by Giorgio Chiellini.
Italy: It all comes down to the final group game now as Italy take on Uruguay on Tuesday. The winner will go through, while a draw would also be enough for the Azzurri due to goal difference.
Costa Rica: Costa Rica will look to make it three wins from three and send England packing with zero points when the two sides meet, also on Tuesday.