Portland Timbers defenders Liam Ridgewell, Alvas Powell and Vytas all sustained injuries in training this week and could be out Sunday when the Timbers travel to face the LA Galaxy.

Vytas is dealing with a calf strain and will miss Sunday's game. He is expected to miss 7-10 days while he recovers. Ridgewell, who is dealing with a foot injury, and Powell, who has an ankle sprain, are "day-to-day" and Timbers coach Caleb Porter did not yet know if the two defenders would be available Sunday.

"None of the three injuries are serious," Porter said. "All of the three may be out this weekend, but I feel pretty good about all of the three being back the following weekend. We also may have two of the three or one of the three back (in time for Sunday's game in LA). We don't know yet."

With Vytas expected to miss Sunday's game, Porter said that 18-year-old homegrown player Marco Farfan would make his debut for the Timbers in the starting lineup at left back. Farfan would become the youngest player to ever make a debut for the Timbers.

"We're very excited about that," Porter said. "Obviously, he's a true homegrown player for us and he will be the youngest Timbers player to ever make a league debut for the club."

If Powell is unable to play Sunday, it is likely that backup right back Chance Myers would take over in the starting lineup. If Ridgewell is unable to go, it is likely that defender Roy Miller would make his Timbers debut.

Miller, who the Timbers acquired from Costa Rican side Deportivo Saprissa in January, arrived in Portland on Tuesday and trained full out with the Timbers for the first time Thursday. Miller previously competed in MLS for the New York Red Bulls.

"He's 90 minutes fit," Porter said. "He's played in this league. We brought him in to be a guy that would cover Ridgewell. He's a left-sided central defender. You never like to throw a guy in the fire with a couple days of training, but if there's ever a guy to play in this situation, it's a guy like him because he knows the league, he's played in this league, he's played in that stadium."

-- Jamie Goldberg | jgoldberg@oregonian.com

503-853-3761 | @jamiebgoldberg