Argentina are looking to maintain their impressive form in the World Cup's group stages when they take on Mexico in the tournament's second round on Saturday, coach Jose Pekerman said. "The game against Mexico will be tough but we have a lot of ambition in this team and we want to keep going," Pekerman said in a news conference on Friday. "The team will go into the match with the same winning attitude as before," he added. The two-time world champions advanced to the knock-out stage after finishing on top of C, following two victories over Ivory Coast and Serbia and Montenegro before a draw with second-placed Holland ensured their status. Pekerman warned his players of underestimating the Mexicans, whose quality could lead to a shocking victory over Argentina. "There isn't a lot of difference between us. Mexico haven't been able yet to show the same form they had in the warm-up games," he said. "But they are a side that can unsettle even the biggest teams, and they can beat anybody. Their players are very fit and very quick. It's going to be a difficult game," he added. There are some injury worries for the Argentineans ahead of the crucial clash, as duo Nicolas Burdisso and Luis Gonzalez is likely to miss the game. "We still haven't decided. We're going to wait until the last minute to see if Nicolas Burdisso and Luis Gonzalez make it, then we'll decide," the former Argentina youth coach commented. Fabricio Coloccini may play as a right-back instead of Burdisso while Hernan Crespo is expected to partner Javier Saviola in the team's front line, after the duo were rested in Argentina's goalless draw with Holland.