D.C. United's final two regular season games this week seem to have little meaning. The club clinched a Major League Soccer playoff berth two months ago, wrapped up first place in the Eastern Conference last month and its starting lineup for the postseason has been set for a couple weeks.

But after an unsatisfying tie for third place at the CONCACAF Champions Cup in Las Vegas last weekend, United has turned serious about tonight's match against the Tampa Bay Mutiny and Saturday's finale against the New England Revolution.

"I just want to see how we respond after the disappointment--see where our psyche is right now, see if we can get this out of our systems quickly," Coach Thomas Rongen said. "As a group, I think we'll respond well and I think we'll be stronger for it. . . . We want to build some momentum for the playoffs. We're not going to experiment. We're not going to rest players. We're going to really fine-tune as much as we can."

United, which has won 11 consecutive MLS games, received some good news yesterday: Leading scorer Roy Lassiter, who injured a hamstring last Friday, responded well in practice and probably will start tonight at RFK Stadium. The only key player missing will be defender Carey Talley, who is serving a one-game league suspension for an accumulation of yellow cards.

The third-place Mutiny won't have forward Raul Diaz Arce, the former United star who still has a large following in Washington's Latin American community. He was recalled to the Salvadoran national team for Gold Cup qualifying games in Los Angeles this week and will miss Tampa Bay's final two regular season games.

Following the disappointment of failing to win the Champions Cup--a title that would have meant a berth in the inaugural world club championships--United's attention is no longer divided.

"We've been concentrating on the Champions Cup for the last two months," forward A.J. Wood said. "We would have liked to win it, but now that it's over, our focus is totally on MLS."

United needs this week's games to work on its team defense and to see if goalkeeper Tom Presthus will regain his all-star form following a poor performance during a 3-1 semifinal loss to eventual Champions Cup winner Necaxa of Mexico last Friday. Presthus was one of nine starters who sat out Sunday's third-place game against MLS's Chicago Fire.

"I have confidence in Tom," Rongen said. "He knows he didn't play well, he knows he let down his teammates. But everyone has embraced him and said, 'Hey, look, we've all experienced something like this, we're behind you.' Tom learned from it and will get better, and it has brought us closer. We win together, we lose together, we're joyous together, we suffer together."

MLS Notes: Washington's Micah Cooks, one of the nation's top college prospects, signed a Project-40 developmental contract with the league. Unlike previous years, Project-40 players will not be assigned to teams; instead, they will attend a scouting combine in Fort Lauderdale, Fla., and be eligible for the league draft Feb. 6.

Cooks, 18, played at the Bullis School and Paint Branch High School, and spent two weeks at Ajax Amsterdam's famed youth school last March. His brother, Judah, is a reserve defender for United. . . .

With two countrymen from each team expected to start, Bolivian ambassador Marcelo Perez will watch tonight's game at RFK from the owner's box. D.C. Mayor Anthony Williams also is scheduled to attend. . . . MLS announced that its 12 teams will begin spring training together for two weeks next year in the Fort Lauderdale-Boca Raton, Fla., area.

united vs. mutiny

Where: RFK Stadium.

When: 7:30 p.m.

Radio: WACA-1540 (Spanish).

Tickets: $13-$34.

Records: United 23-7, 57 points; Mutiny 13-17, 29 points.

D.C. Probable Starters: GK -- Tom Presthus; D -- Diego Sonora, Eddie Pope, Carlos Llamosa, Jeff Agoos; MF -- Richie Williams, John Maessner, Ben Olsen (5 goals, 11 assists), Marco Etcheverry (4, 17); F -- Jaime Moreno (10, 13), Roy Lassiter (17, 11).

Mutiny Top Players: F Musa Shannon (11 goals, 5 assists), MF Steve Ralston (4, 16), MF Carlos Valderrama (4, 13), MF Mauricio Ramos.