HOUSTON -- Rather than address Steve Pearce's left knee tendinitis with surgery, the Pirates are hopeful that an injection will suffice.

Dr. Patrick DeMeo examined Pearce in Pittsburgh on Tuesday and recommended that he have a platelet rich plasma injection into his patella tendon on Wednesday. Pearce had been diagnosed with patella tendinitis last Friday after having an MRI done on his left knee in Indianapolis.

Following seven-to-10 days of inactivity after the procedure, Pearce will be able to resume treatments and exercises. Still, general manager Neal Huntington estimated that Pearce will not be able to return to game activities until early August at best.

If the PRP injection does not produce desired results, surgery would be the next consideration. It'll likely take four-to-six weeks to determine the success of the injection and how well it is controlling Pearce's symptoms.

Knee pain forced Pearce to stop playing last week while he was with Triple-A Indianapolis finishing up a rehab assignment for a sprained right ankle. Pearce has dealt with achy knees before, but until now, he had always been able to play through the discomfort.

"It got to a point where it really flared up," manager John Russell said. "Hopefully this works and gets him back."

Even if Pearce is able to avoid surgery and return to the field next month, this injury is cutting into the time the Pirates have to determine if the first baseman might fit into the club's long-term plans. Pearce will be out of options after this season and still hasn't had the chance to play regularly in Pittsburgh for any lengthy stretch of time.

At the time he sprained his ankle in late May, Pearce was 8-for-29 (.276) with five RBIs in 15 games with Pittsburgh.

Duke makes first rehab start

HOUSTON -- Zach Duke needed just 29 pitches to finish three innings in a Minor League rehab start with Double-A Altoona on Monday.

Duke, who is on the disabled list with a left elbow flexor pronator strain, allowed three hits, one run and struck out one in the outing. The Pirates planned to allow him up to 50 pitches in the three-inning stint, but Duke's efficiency kept his final pitch count much lower.

"The biggest thing is he made it through and felt good," manager John Russell said.

The left-hander will start again for Altoona on Saturday, this time being stretched out to five innings (65 pitches). If all goes well with his side session this week and that start over the weekend, Duke is expected to be reinstated from the DL after the All-Star break.

Duke last pitched for the Pirates on June 16. He was 3-8 with a 5.49 ERA in 14 starts before going on the DL for the first time since 2007.

Cedeno out of lineup, working on approach

HOUSTON -- Though manager John Russell hasn't gone so far as to designate Bobby Crosby his everyday shortstop, it has become plenty evident that Crosby will continue getting the majority of playing time there until Ronny Cedeno can show specific improvements in his approach at the plate.

Crosby started at short on Tuesday for the 15th time in the team's last 19 games. Cedeno has made the other four starts during that span, though two of them came when Crosby was unavailable because of concussion-like symptoms.

Crosby has done his part to earn more regular playing time by going 12-for-36 in his last 11 games. However, his inclusion in the starting lineup is just as much of a result of Cedeno's inability to show a more consistently aggressive approach at the plate. That's something that hitting coach Don Long has been preaching to Cedeno all season.

"The biggest thing is using his talent," Russell said. "He has a quick bat. He can drive the ball. I think he gets in situations where he tries to force the ball. Then you limit yourself so much. Donny and I talked to him about staying back, seeing the ball and staying aggressive. We'll see if that will play for him."

Cedeno went 0-for-3 after being given the chance to start on Sunday. He has only eight hits in 70 at-bats since May 29.

"It's going to be a process to get him a little more comfortable," Russell said. "[He needs to] just see the ball and be aggressive."

Worth noting

Tuesday's contest against the Astros marked the first of 13 straight games the Pirates will play against Houston and Milwaukee. The Pirates entered this series 3-8 against the two National League Central clubs so far this season. ... In his first start since coming off the disabled list, Charlie Morton allowed three earned runs on four hits in five innings on Sunday. Morton struck out two and walked three. ... Left-hander Dana Eveland, who was designated for assignment on June 23 and sent outright to Triple-A, lasted just 2 1/3 innings in his start for Indianapolis on Monday. He allowed five earned runs on six hits, two of which were home runs. ... Right-hander Jeff Sues (Double-A) has been put on the disabled list with a right ankle sprain. ... Anthony Claggett, who pitched briefly with the Pirates last season, has been demoted from Triple-A to Double-A. The 25-year-old right-hander allowed 26 earned runs in 45 2/3 innings (28 appearances) with Indianapolis this season.