Lionel Messi poses problems for every team, a fact Switzerland coach Ottmar Hitzfeld prefers to think of as an opportunity.
Messi has scored four of Argentina's six goals, steering his team to three group-stage wins.
But Hitzfeld, a two-time Champions League winner as a coach, struck a confident tone ahead of Switzerland's second-round World Cup match Tuesday, particularly regarding the player many consider to be the best player in the world.
"I think any defense will face problems when facing Messi and problems are there to be solved," he said. "I trust my people, I trust my defense ... How to stop Messi? We will show you tomorrow how we do it."
Under Hitzfeld, Switzlerand lost only once in 18 matches over the two years leading up to the World Cup and reached No. 6 in the FIFA rankings. That earned them top seeding in Group E.
A win over Argentina would equal Switzerland's greatest World Cup achievement, putting them in the quarterfinals for the first since it hosted the tournament in 1954.
Hitzfeld, a 65-year-old German who says he will retire following the World Cup, told reporters Monday: "I don't think it is going to be my last match."
"We, Swiss team, have become stronger over the last two years and I'm quite interested and looking forward to this sporting highlight that we will see tomorrow," he said.
A team that earned a reputation for a boring brand of football in the 2006 and 2010 World Cups has reinvented itself under Hitzfeld. Its star player, Bayern Munich's Xherdan Shaqiri, has earned the nickname "the Alpine Messi."
The 22-year-old Shaqiri, born in Kosovo to Albanian parents, scored a hat trick to put the Swiss into knockout stages with a 3-0 win over Honduras.
"He is short, he is fast, he is mobile," Swiss captain Gokhan Inler said of Shaqiri. "The good thing for us is that he can't be figured out easily."
Switzerland also beat Ecuador 2-1 in the group stage, but was routed by France in a 5-2 defeat.
Against Argentina, the Swiss also expect an extra boost from Brazilian fans in Sao Paulo, who will likely want to see their top South American rival knocked out of the competition.
Inler said the fan support will be helpful, and vowed: "We are ready to face a great team like Argentina."
Follow Heller on Twitter @aronhellerap