RENTON — Training-camp battles are a staple of preseason.

But with Sounders FC returning several starters from last year, and having already replaced a couple of losses in the offseason, not many positions in the lineup appear up for grabs.

Perhaps the fiercest head-to-head competition will be at left back between Leo Gonzalez and Marc Burch, and one week into preseason, coach Sigi Schmid isn't tagging anyone as the starter.

"We're going to have depth there and we're going to have options," he said, "but I'm confident in Leo playing there and I'm confident in Marc."

Left back was a position assumed by committee last season, with Tyson Wahl playing most of the MLS minutes and Gonzalez participating more in the U.S. Open Cup and CONCACAF Champions League.

Wahl was traded to the expansion Montreal Impact in the offseason, and soon afterward Seattle acquired the 27-year-old Burch in the MLS Re-Entry Process. With the Sounders' first game in six weeks, the battle for the No. 1 spot is already well under way.

"Anytime a player comes, as long as they come to contribute to the team, the competition is always going to be healthy," said Gonzalez, 31, through a translator. "It's always going to add to the team."

Added Burch: "I know Leo and Tyson split some time last year and I could expect to see the same thing, but you never know with injuries, with how teams are playing, momentum. We play a lot of games, so I think there will be opportunities for both of us, and whoever plays the best should be in the starting lineup."

Since signing midway through the 2009 season, Gonzalez has started 50 games for the Sounders. Schmid said the Costa Rican, who came into camp in great shape after dealing with hip issues last year, has the edge over Burch in one-on-one defending.

A converted forward, Burch is a better with the ball and has recovered well from offseason toe surgery, according to the coach.

And how are they similar?

"They're both not afraid to get a little bit physical when they need to," said Schmid. "So from that standpoint they're pretty equal."

Which won't make naming a starter any easier.

Notes

• Another position battle is at center forward, where Sammy Ochoa, Mike Fucito and draft pick Babayele Sodade are competing to play alongside Fredy Montero. Schmid said a lack of depth at forward will require either Roger Levesque or David Estrada to play more up top.

• The Sounders held their annual preseason sprint test Friday at the Virginia Mason Athletic Center. Invitee forward Darwin Jones, formerly of the team's youth academy, finished first in the 30-meter dash. He was followed by forward/midfielder Cordell Cato, draft pick Abdul Aman, Fucito and Danish midfielder Christian Sivebaek.

Joshua Mayers: 206-464-3184 or jmayers@seattletimes.com.

On Twitter @joshuamayers