Toronto FC midfielder Dwayne De Rosario, middle, has one goal in five games this season. (Tony Gutierrez/Associated Press)

Toronto FC could be without star playmaker Dwayne De Rosario for several weeks due to a hamstring injury suffered in Sunday's game, the team announced Tuesday.

And to add insult to injury, head coach John Carver was fined by Major League Soccer for criticizing the officiating during the same match.

De Rosario, a native of Scarborough, Ont., is scheduled to have a scan to determine the extent of the injury, which he suffered in the 3-2 road loss to FC Dallas.

"He's definitely out for two [games] and it might be more than that," Toronto coach John Carver said Tuesday.

Acquired by Toronto in an off-season trade with the Houston Dynamo, De Rosario sat out practice last Friday as a precaution before aggravating the injury in the Dallas game.

"I think building up to the game on Sunday, it was an issue of he just had a tight hamstring," Carver said. "You saw from his reaction he did tear it. To what degree, we're going to find out once he has a scan. But he has a tear in there and that can be anywhere [from] three to four weeks.

"So I won't put him under any pressure to get him back, although I could do with him on the pitch."

The loss of De Rosario, a three-time all-star, is a big blow to a Toronto team that won its first game of the 2009 Major League Soccer season, but is winless (two losses, two ties) in its last four contests.

Any prolonged absence would be detrimental to Toronto's playoff hopes, too. The Canadian club acquired the veteran playmaker to help them make the post-season for the first time since entering the league in 2007.

Carver fined for comments

Carver was fined $750 US by MLS later Tuesday for calling referee Tim Weyland's performance "a disgrace" in the weekend loss to FC Dallas.

The game was decided by an 84th minute penalty kick to give Dallas a 3-2 victory. It was a controversial decision by referee Weyland, who concluded that Toronto defender Marvell Wynne intentionally handled the ball with his arm in the 18-yard box.

"I'm having a go at the referee today because his performance was a disgrace," Carver told the Toronto Star on Monday.

"Now, you tell me how a guy who's running flat out can change direction having to have his arms down by his side. It's impossible. I'm sure the referee couldn't change direction with his hands in his pockets."

Toronto hosts Chivas USA on Wednesday and welcomes the Kansas City Wizards to town Sunday.

With files from The Canadian Press