FRISCO, Texas – FC Dallas may rest George John (above) for a big matchup in Seattle on Saturday, due in part to the risk of a potential injury to the club's prized central defender on CenturyLink Field's artificial turf surface.

“It’s going to be a decision we have to make [Wednesday] or early Thursday if we’re going to bring him or not,” FC Dallas head coach Schellas Hyndman told reporters on Tuesday. “If it was a grass field, I think we’d feel a lot more comfortable with it, but being that he had a knee injury and now we’re back on turf, I have to look at the bigger picture of the rest of the season.”

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John has appeared in nine of the team's 11 games this season, all of which were starts. He also has two goals to his credit this year while helping lead FCD to the best record in Major League Soccer.

In addition to John, David Ferreira and Andrew Jacobson each sat out last Saturday’s 2-1 victory over D.C. United nursing injuries. After the match, Hyndman told reporters that Jacobson could have played that night, but that he doubted he’d have been able to go if the match that night was in Seattle as the turf could have made his injury worse.

“The problem with the turf is you pick up silly injuries,” Hyndman said. “You’d be surprised how much it wears your calves and legs out. Now, if you’re playing on turf all the time, you get used to it. It’s like playing at altitude all the time, you get used to it.”

At Tuesday’s practice, John and Jacobson each did light work on the side to avoid contact and limit explosive moves, but Ferreira sat out altogether.

“David Ferreira, we decided yesterday to keep him out of training, so we’ll have to wait and see how he’s progressing [Wednesday],” Hyndman explained.

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The team will train on its own artificial practice surface Wednesday and again on Thursday before flying to Seattle, where they have won just one of four games all-time.