The Sounders trained today at Qwest Field, but neither goalkeeper Kasey Keller nor forward Fredy Montero was around for the finish.
Montero was sent home immediately when he reported with what is described as a low-grade fever.
Keller started practice but went off the pitch with an apparent left-ankle problem.
"(Keller) just trained a little bit today, and was a little bit sore," coach Sigi Schmid said. "And we said just go on in early and take care of it. So we feel fine. He’ll be ready to go on Thursday. His ankle was a little bit sore today."
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"Fredy had a low-grade fever, so we wanted to keep him away from the team. He came in, but we said, ‘No, go home.’ We just sent him to the doctor and sent him home. We just wanted to be sure with a low-grade fever that nothing was going to happen."
Keller and Montero were both MLS All-Stars this season. Keller ended the regular season with the league's second-best goals-against average, while Montero was third with 12 goals and led the league in shots taken.
Sounders reserve keeper Terry Boss said he expects Keller to play Thursday, but that he feels ready whenever needed.
“Health-wise we’re good," Schmid said. "We have 23 players that are all training right now. We’ve got three goalkeepers and only one of those isn’t training (Chris Eylander). So out of 26 players we have 25 players training, which is good.”