When and where: The Olympic soccer first round Group B match kicks-off from the Millennium Stadium in Cardiff, Wales at 12.15 p.m. ET. Coverage will be provided by the NBC Sports Network, with a live stream available at NBCOlympics.com.

Preview: Both Mexico and Switzerland head into the final match of Group B with their fates very much in the balance. Though Mexico top the standings, they still need a point to ensure their progress through to the quarterfinals. While that could pose a dilemma for El Tri, there is no such uncertainty for the Swiss. After surprisingly taking just a single point from their opening two games, Switzerland need to win to stand a chance of keeping their medal hopes alive.

After an opening goalless draw with Korea, Mexico cast aside Olympic debutantes Gabon 2-0. For the second game in succession, Giovani dos Santos was forced to start the match on the bench, despite being a mainstay of the full international setup. The Tottenham forward showed his value, though, as he come on at half-time to score both goals.

Coach Luis Fernando Tena will be under significant pressure to bring Dos Santos into his starting lineup for the match in Cardiff. Tena has other selection difficulties as well ahead of the vital clash. Key midfielder Hector Herrera suffered an injured ankle against Gabon and is a major doubt to take part on Wednesday, while Javier Aquino is also an injury concern.

The Swiss already know that they will be without a member of their ranks for the contest. Following their match with Korea, defender Michel Morganella was sent home after a posting a racist comment on Twitter.

Following a disappointing draw with Gabon and a defeat to Korea, the unsavory and disruptive incident was the last thing that coach Pierluigi Tami will have wanted.

Prediction: Fancied by many before the tournament to challenge for medals, Switzerland have failed to fulfill expectations raised by finishing runners-up in last year's European Under-21 Championships. After the controversy in recent days, it is difficult to see the Swiss turning things around for this crucial encounter.

Mexico should have the quality to get the win they need to try and ensure top spot in the group.

Mexico 2-1 Switzerland