The England midfielder suffered what he has described as a "ligament strain" in his right knee during his team's SuperLiga trophy final defeat against Pachuca in Carson and is set to undergo a scan tomorrow which will reveal the full extent of the damage.

Beckham sustained the injury in a first-half challenge with Pachuca's Fernando Salazar and limped off.

Beckham looks set to miss England's vital qualifiers with Israel and Russia at Wembley on September 8 and 12 unless the scan brings good news.

Beckham said: "At the moment, we`re calling it a ligament strain, but in the morning I'm going for a scan to see exactly what it is and how long I'm going to be out.

"But at the moment, it doesn't feel great.

"This is a injury that takes 4 to 6 weeks, but who knows, if the scan is not so bad maybe I`ve got a chance to play (for England). We'll know more tomorrow."

Beckham suffered the injury in the 31st minute as both he and Salazar simultaneously made strong contact with the ball.

He looked to have jarred his right knee and rolled on the ground in obvious pain. He slowly stood up and motioned to the bench before limping off the field.

Galaxy physio Ivan Pierra helped the 32-year-old back to the Galaxy bench while coach Frank Yallop sent on Alan Gordon as a replacement.

The former England captain revealed that a desire to protect his ankle, which until recently had kept him out of action, had caused him to go into the tackle differently to when fully fit.

"I went into the tackle a little light because of my ankle and tried to compensate for that," he said.

"I`d have been better off not doing it at all."

If Beckham's worst fears are realised by tomorrow's scan he could also be a doubt for the qualifiers against Estonia at Wembley, on October 13, and Russia in Moscow four days later.

Yallop admitted he feared for his skipper as soon as he failed to get up following the challenge.

"At first, I was worried for David because it looked like it was his knee - he usually gets up pretty quickly and he didn`t so I made the sub. We'll know more tomorrow," he said.

Galaxy have an MLS match against Real Salt Lake on Saturday and Beckham has already missed eight of Galaxy's 12 games since he joined the club on July 13.

Beckham watched from the sidelines as Chris Klein scored a last-minute equaliser for Galaxy to force the final into extra-time, with Pachuca eventually winning 4-3 on penalties to claim the SuperLiga trophy and one million US dollars.

He played 90 minutes for England in the friendly defeat against Germany at Wembley on August 22 and 90 minutes for Galaxy a day later but did not travel to Colorado for Sunday's league match.

Beckham had started the game looking as fit as he has at any time since joining Galaxy and creating several early chances.

Finding himself unmarked on the right flank in the seventh minute he swung a cross into the heart of the penalty area but Landon Donovan headed over.

Pachuca went ahead in the 28th minute when Peter Vagenas, attempting to clear a Christian Gimenez cross, sliced into his own net.

Klein's late leveller sent the match into extra-time but they lost the subsequent penalty shoot-out when Abel Xavier dragged his spot-kick wide.