COLLEGE PARK, Md. — The US national team's highest-profile player is not ready to start against the highest-profile opponent in the five-game series of matches over the next two weeks.

Fulham star Clint Dempsey participated in full training during an open practice session held on Memorial Day Monday at Ludwig Field on the grounds of the University of Maryland. But with a massive matchup against Brazil looming on Wednesday night (8 pm ET, ESPN2, TeleFutura, LIVE CHAT on MLSsoccer.com), he admitted he's still playing catch-up with the rest of the group after a layoff to nurse a right groin injury.

"No, I couldn’t [start]," Dempsey responded when asked if he would be ready to start if called upon by Klinsmann on Monday. "I don’t think I’d be able to go a complete 90 minutes and I don’t think you should put yourself in the position to take up a spot of a guy who has more fitness than you. But I’m going to continue to work hard and try to get my fitness up and if I do get into the game, I want to make an impact."

Dempsey has given US fans some of their most thrilling moments against Brazil. He scored the goal that gave the US a momentary 2-2 tie in a friendly in Chicago back in 2007, and also scored the opening goal in that crushing 3-2 loss to the Seleção in the 2009 Confederations Cup final.

The issue ahead of this latest matchup is less about the groin and more about match fitness in the words of Dempsey, who said he "felt sharp on the ball" during Monday's training. He left a glimmer of hope he could still recover in time for a start on Wednesday.

But just a glimmer.

"You always want to play against top teams," Dempsey told the media on hand. "It’s always exciting, but at the same time you don’t want to go back unless you can feel you can make an impact. I think if I get another training session under my belt and see how things go and push myself a little bit further, I know whether I’ll be ready."