"We're still hopeful there are no issues or anything structurally wrong," assistant general manager Thad Levine said. "Unfortunately, we don't know what's going on and we need to get more information."
Otsuka had said before the game that he was ready to go. That proved not to be the case, and the Rangers found out right as they were breaking this game open with a five-run seventh inning that gave them a 10-4 lead.
The Rangers, having won three straight and 18 of their last 28 games, are now within 2 1/2 games of the third-place Athletics in the American League West.
"I'd rather be shooting for first place," first baseman Mark Teixeira said. "But we're playing well and having fun right now together as a team. That's the big thing."
The Rangers have now won six of their last eight series, but they go for only their second sweep of the season in Game 3 on Wednesday afternoon. The Athletics have now lost nine in a row, their longest losing streak since 1998. But the Rangers, having been through something like this in May, aren't feeling sorry for the Athletics, their trying to take advantage of their misery.
"You have to," outfielder Marlon Byrd said. "It's not like you say 'We've won two, now you can have the last game.' It doesn't work like that. You've got to keep going."
The Rangers did everything right but hit the ball out of the ballpark. They did not hit a home run, but still had 15 hits, including triples by Kenny Lofton and Ramon Vazquez. They drew eight walks, hit two sacrifice flies, moved runners over with a couple of bunts and stole a base.
They were 6-for-15 with runners in scoring position after coming into the game with a .202 average in those situations for the month of July.
"We did a lot of everything tonight," Teixeira said. "We got some big hits. They helped us out by walking too many guys and didn't make some plays, but we capitalized on them."
Teixeira had four of the Rangers' eight walks and was also hit with a pitch on his left quadriceps muscle. That's the muscle that had him on the disabled list for over a month, but Teixeira said he was fine.
"It just stung," Teixeira said.
Michael Young was the real leader of the Rangers offense against Oakland starter Chad Gaudin, with going 5-for-5 with a walk, two doubles and three RBIs. He has three doubles in his last two games after going a month without an extra-base hit.
"I was never worried about that," Young said. "It didn't have any effect on me at all. The fact that the five hits came on a night when everybody contributed was the best part. Offensively, we played well. We knew we had our work cut out for us in Gaudin. He's a great pitcher having a great year and was tough early on. But we chipped away and got some breaks."
Lofton had three hits and the bottom third of the Rangers order -- Gerald Laird, Vazquez and Jerry Hairston -- were a combined 4-for-13 with a walk, six runs scored and three RBIs.
"That's a better team than its record over there, for sure," Oakland manager Bob Geren said. "But we let the game get away in that one inning, and we couldn't get it stopped after that."
Rangers starter Robinson Tejeda, pitching for the first time in 12 games, had his own troubles, walking six in 4 1/3 innings. That tied a career high.
He was given a 3-1 lead in the top of the fifth, but the Athletics tied it in the bottom of the inning on a two-run home run by Jack Cust. Tejeda was gone after allowing a one-out infield hit by Bobby Crosby.
"I just didn't want to let the game get out of hand," Rangers manager Ron Washington said. "He was having problems with his command. He hung in there and fought hard, but just didn't have his command."
Willie Eyre picked up the win with relief help from C.J. Wilson and Ron Mahay, who pitched three scoreless innings for his first save of the season and fourth of his career.
The bullpen continues to be big strength for the Rangers. They'd just like Otsuka to be back and a part of it.