TUKWILA, Wash. — Just as Osvaldo Alonso is set to rejoin the Seattle Sounders, injuries will again keep them from fielding an ideal starting lineup.

Leading scorer Obafemi Martins has been all but ruled out for the team’s matchup against the San Jose Earthquakes on Saturday (10:30 pm, MLS Live/Free Stream on MLSsoccer.com), and midfielder Shalrie Joseph is doubtful for the game with a nagging calf injury.

Sounders head coach Sigi Schmid told the media on Friday that Martins – who has scored six goals this season - is still recovering after being kicked in the calf during the team’s loss to Vancouver last weekend, adding, “Oba's probably not going to play.”

As big of a loss as Martins would be, however, the return of Alonso may be enough to counterbalance it against the Quakes. He has not played since a 2-0 win over Chivas USA on June 1, but he gave the impression Friday that he intends to play this weekend after recovering from a quadriceps injury.

“I’ve been training the past two weeks,” Alonso said. “I feel good for Saturday.”

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The Sounders have won each of the past five games Alonso has started and have gone 5-2-2 with him in the starting lineup this season. The last time Alonso was healthy enough to play a full match, in fact, came against the Earthquakes, a game the Sounders won 4-0 on May 11.

Alonso’s presence is especially apparent on defense, where the Sounders have allowed just five goals in his 682 minutes (a rate of .66 per 90 minutes), as opposed to 14 goals in 758 minutes without him (1.66 goals per 90).

Although Servando Carrasco has done an admirable job filling in, the statistics suggest Alonso is virtually impossible to replace.

“We know when he plays that the players in the middle have more freedom because he can cover a lot of ground,” Sounders center back Djimi Traore told MLSsoccer.com about Alonso. “He’s a hard worker. To be honest, we have a lot of good players but no one does as much as he does and he’s a good influence on the middle of the park. He’s very important for us.”