SAN DIEGO -- Early Tuesday, the Padres were somewhat optimistic upon learning that pitcher Jake Peavy, though in need of two more weeks in his protective boot, is improving.

But the organization's glass-is-half full attitude all but disappeared in the bottom of the fourth inning when star player Adrian Gonzalez left the field after a rare triple.

Characterizing Gonzalez's injury as a strained right knee, the Padres said they are uncertain how long their All-Star first baseman will miss. His injury somewhat dampened the dramatic 4-3 victory over the Houston Astros the Padres put together after Gonzalez departed.

The victory included a three-run rally from a 3-1 deficit in the seventh inning, but it will leave a bitter taste if Gonzalez misses a significant amount of time.

"It's too soon to tell. We're going to send out results overnight," Padres manager Bud Black said of Gonzalez's injury. "There's obviously some soreness. He tweaked some muscles around the knee. But the doctors couldn't come up with a concise diagnosis. We'll know more tomorrow."

What they knew Tuesday was that Gonzalez wasn't feeling right. After several pitches to Kevin Kouzmanoff, third base coach Glenn Hoffman signaled for trainer Todd Hutcheson to come inspect Gonzalez. Gonzalez then ran up and down the third-base line several times before he was pulled from the game, leaving the field under his own power. Afterward, Gonzalez was upbeat enough to joke as he described the injury, which he said was a tweaking of muscles as opposed to structural damage. He said he would only get an MRI on Wednesday if he awakes in pain.

"I hardly even played," Gonzalez said. "… It was tough running on it and, a couple of times where my knee locked up, it really hurt. I was trying to stay away from locking it up and putting pressure on it, but Hoffy saw me kind of struggling with it."

Already without their Nos. 1 (Peavy) and 2 (Chris Young) starting pitchers and No.3 hitter Brian Giles, the Padres can ill afford the absence of Gonzalez. The team is fortunate enough to have its top prospect, first baseman/left fielder Kyle Blanks, already in town. However, the loss of Gonzalez, who has a team-high 24 homers and 48 RBIs, would be damaging to a lineup that entered Tuesday hitting .236 with a major league-low 287 runs scored.

"I don't think it was anything major, because he walked off the field by himself. So maybe it's just a couple days rest," said closer Heath Bell, who pitched the final 1 1/3 innings for his 22nd save. "If that's the case, Kyle Blanks is going to have to step it up and have a couple more hits like he did in Texas."

As it is, the Padres trail the National League West-leading Los Angeles Dodgers by 14 games and the wild-card leading San Francisco Giants by eight games. When asked prior to the game if the Padres would be buyers or sellers leading up to the July 31 nonwaiver trade deadline, Padres general manager Kevin Towers said: "I'll let you determine that."

Towers said he thinks pitchers Kevin Correia and Chad Gaudin, both of whom will have nearly five years of service time at the end of 2009, will draw interest from contending teams because they're affordable options. Correia, who signed a minor-league deal and is earning $750,000, is 4-1 with a 2.41 ERA in his last five starts, striking out 29 and walking three over his last 33 2/3 innings.

Gaudin, who is earning the major league minimum, was named the NL's co-player of the week on Monday after winning two starts and striking out 20 in 15 innings. The team also could see offers for arbitration-eligible players Kouzmanoff and Scott Hairston as well as second baseman David Eckstein, who drove in the game-winning run against Chris Sampson (4-1).

Towers assumed that Gonzalez -- who he has deemed untouchable at this point -- will draw heavy interest. The Tampa Bay Rays have reportedly inquired about Bell, who tied Brian Fuentes for the most saves in baseball. But sources said the Padres aren't currently interested in trading Bell.

The team also could see more offers for Peavy, who could return by late July.