PHOENIX -- General manager John Mozeliak said on Friday that the Cardinals received "positive news" on right-hander Brad Penny earlier in the day, but stopped short of projecting a date for Penny's return to active duty or even to pitching off a mound.

Penny, who has been out since May 21 because of a strained right lat muscle, underwent an MRI exam which showed improvement in the injury.

"He's continuing to progress, but having an end date for when he'll be back, I've been wrong so many times, I'm just going to stay out of the guessing game," Mozeliak said. "What the MRI showed was significant improvement, and based on that, we're just going to continue down that path."

Penny has remained on a throwing program, but has not thrown off a mound since he was sidelined.

"He threw one day in L.A., but it just didn't sound like we were getting to where he was really getting any closer, so we decided to go back and do a study on him and let it be less subjective," Mozeliak said.

Suppan inching closer to deal with Cards

PHOENIX -- Jeff Suppan has a flight headed west. He has an empty locker with his name hanging over it in the visitors' clubhouse at Chase Field. What he still doesn't have just yet is a signed, completed contract with the Cardinals.

Suppan, recently released by the Brewers, will throw for St. Louis on Saturday afternoon at Chase Field. If he shows he is healthy, it is all but certain that he will join the club, possibly to start as soon as Tuesday at home against the Mariners. The Cardinals have already cleared space on their 40-man roster for Suppan, outrighting Minor League left-hander Tyler Norrick.

"This [throw] is really just for where he is physically, and just to allow us to have an idea of what he can really do physically," general manager John Mozeliak said. "And ultimately be a little bit of a working session.

"The reason we haven't signed him or made it, quote, 'official' is, A, he's not here, which is always why you don't do things like that, because it's premature. And B, we just want to make sure where he is physically. Obviously, you want to make sure you do your due diligence before that. But it's not where we're making him come in here and show that he is good enough."

Suppan was initially slated to throw for the Cards on Friday, but travel delays pushed back his session.

Two members of the Cardinals' starting rotation -- Brad Penny and Kyle Lohse -- are currently on the disabled list. Adam Ottavino will start on Saturday in Phoenix, but Tuesday's starter remains unannounced at this point. P.J. Walters has scuffled since a fine 2010 debut in San Diego, and Blake Hawksworth didn't fare much better in a start on Monday night against the Dodgers.

Thus, Suppan, whose numbers have suffered since he left St. Louis, but who enjoyed success while a member of the Cardinals.

"We have a history with him, he's available, and I think [pitching coach Dave Duncan] has seen some things that make him think that there's some 'Supp' left," manager Tony La Russa said.

Rasmus back; Freese close behind

PHOENIX -- The Cardinals got one key cog in their offense back on Friday, and another is likely to return Saturday or Sunday.

Colby Rasmus, bothered by a sore left calf, returned to action on Friday night after sitting out the Cards' entire series against the Dodgers. David Freese, dealing with a right ankle injury, has been cleared to hit and run the bases, but is still a day or two away from playing defense.

"We're just making sure the lateral movement, defensively, [is not a problem]," Freese said on Friday afternoon. "I feel pretty good."

Rasmus and Freese rank second and third on the Cardinals, respectively, in on-base percentage, so it's not entirely a coincidence that the team's offense went cold during the Dodgers series. On Friday, Rasmus not only returned to the lineup, he was bumped up to the No. 2 spot in the batting order.

Ryan Ludwick, who had been hitting second before Freese's injury, remained in the No. 5 spot, where he was moved when Freese went down.

Baby Birds

Jon Jay homered and walked and Brandon Dickson pitched seven strong innings as Triple-A Memphis beat Iowa on Thursday, 7-2. Daniel Descalso and Allen Craig also had two hits each for Memphis. ... Tyler Henley homered for Double-A Springfield, but the S-Cards were done in by three unearned runs and some shaky bullpen work in a 7-3 loss to Tulsa. ... Tony Cruz went 3-for-5 with an RBI in Class A Palm Beach's 3-2 loss to Charlotte. ... Robert Stock singled, doubled and drove in two runs for Class A Quad Cities in a come-from-behind, 7-6 win over South Bend. The River Bandits trailed, 6-1, in the sixth.

Player of the day honors go to Dickson, who made it five straight excellent starts by allowing a run on seven hits over seven innings. He struck out five and walked one. Dickson has gone five straight starts of at least six innings with no more than two runs allowed. On the year, he's 7-3 with a 3.16 ERA, 52 strikeouts and 24 walks in 13 games (12 starts) for Memphis. The 25-year-old right-hander signed with the Cardinals as a non-drafted free agent in 2006 and has steadily progressed through the ranks.

Worth noting

General manager John Mozeliak and manager Tony La Russa both said that St. Louis does not have any real interest in former Cardinal Brad Thompson, who was recently let go by the Royals. ... Mozeliak will attend Saturday night's NCAA super regional game in Tempe, Ariz., which will feature three of the Cards' first four picks from this week's First-Year Player Draft. ... Monday's series opener against the Mariners will start early due to ESPN's broadcast. The game is set for a first pitch of 6:09 p.m. CT.