LOS ANGELES -- Cardinals manager Tony La Russa said Tuesday that the club could look for outside help to improve its starting rotation with right-handers Brad Penny and Kyle Lohse on the disabled list but that nothing is imminent.

"We have to get a feel for how long Penny is out before we have serious discussions but [Cardinals general manager John] Mozeliak stays on top of that," La Russa said. "I just don't think it's good for us to get caught up in it. We have to play with what we've got and let the guys up here know they can help us until the other guys get back."

The Cardinals have been leaning on right-handers Adam Ottavino, Blake Hawksworth and P.J. Walters to fill in the gaps in the rotation but the trio has combined for a 1-4 record and 6.71 ERA this season.

Walters was also optioned to Triple-A on Tuesday, leaving Ottavino and Hawskworth in the rotation for at least the next week.

"I'm confident that Moz and our scouts are staying abreast of our situation but honestly I don't think anything will show up before next week when we play Seattle," La Russa said. "You just can't give the club the vibe that things aren't fair right now. These games still count."

Cards call up Salas, send down Walters

LOS ANGELES -- A day after he allowed six runs in four innings of relief work, Cardinals right-hander P.J. Walters was optioned to Triple-A Memphis on Tuesday and rookie right-hander Fernando Salas was recalled from Triple-A to take his place on the roster.

Walters, who was 1-0 with a 7.94 ERA in two relief appearances and two starts, simply didn't throw enough strikes, as he walked eight batters in 17 innings.

"Right now, P.J. is a control pitcher who has been falling behind the count," Cardinals manager Tony La Russa said. "That's why he needs to throw a little a bit."

Salas, meanwhile, was recalled for the second time in two weeks, as he made one relief appearance on May 28 against the Cubs, throwing a scoreless inning in his big league debut.

Salas was 1-0 with a 2.82 ERA in 23 appearances in Triple-A this season with 23 strikeouts and four walks over 22 1/3 innings.

Rasmus, Freese remain on sidelines

LOS ANGELES -- Cardinals center fielder Colby Rasmus and third baseman David Freese were out of the starting lineup yet again on Tuesday and aren't expected back until Friday against the D-backs in Phoenix.

Rasmus, who also missed Monday's game with tightness in his left calf that caused him to leave Sunday's game against the Brewers in the sixth inning, received treatment on his injured calf but has yet to participate in running drills.

"He's better but I don't think he's 100 percent," Cardinals manager Tony La Russa said. "I don't think he'll play tomorrow. I doubt it."

Freese hasn't started since Saturday because of a sprained right ankle but served as a pinch-hitter on Sunday and Monday and will still be available in that role.