Federer battling for semifinal birth at Masters Cup

By the time he takes the court at the $4.45 million Tennis Masters Cup on Friday, Roger Federer will know if he is on the brink of elimination.

In what could amount to a do-or-die match for him, the world No. 1 will face American Andy Roddick in the final round-robin match for both players at this season-ending event.

Federer (1-1, Red) will secure the remaining semifinal spot here with a win over Roddick (2-0) or if Nikolay Davydenko (0-2) defeats Chile's Fernando Gonzalez (1-1) in Friday's opening Red Group match.

The defending champion and a three-time winner of this indoor hardcourt event, Federer's doomsday scenario would be a loss to Roddick and a win by Gonzalez - who would claim the remaining semifinal spot if things broke that way.

The 26-year-old Federer, who is fighting for contention as a result of losing his opening match to Gonzalez, definitely has the odds working in his favor.

The 12-time Grand Slam winner has beaten Roddick in 10 consecutive matches and is 14-1 in the all-time series. If that wasn't enough, Gonzalez has never beaten Davydenko in three career meetings.

"There's no reason for me to be nervous," Roddick said. "I can go out there and let it fly. The way I see it on Friday, I can just go out there and play and go for my shots and play aggressive and try to knock him out. I'm sure I'll have about seven other guys cheering for me to do that."

While already into the round of four, Roddick does have something to play for - first prize here is $700,000, but if the champion goes undefeated he will receive a total of $1.52 million.