ST. LOUIS -- Closer Huston Street, who has missed the past 17 games with a strained right lat muscle, threw on sidelines for the fifth day in a row on Wednesday.

Street says his rehabilitation is "on schedule" and he is anxiously waiting the next step.

"It's progressing nicely and I'm ready to start pushing it," Street said.

Street will stretch out and go through some long-toss exercises later in the week. He hopes to graduate to a bullpen session early next week. He is with the team on its current 10-game road trip.

Padres manager Bud Black said that Street will likely need a pair of Minor League rehab outings before he can rejoin the team.

"He's getting closer to the mound," Black said.

Street, who was injured in the tenth inning of a 9-8 loss to Miami on May 4, is taking a cautious, yet optimistic, approach to his rehab.

"It's a tough muscle and you don't want to try and do too much," Street said. "You've got to be patient and do the right things. Three or four extra days can mean the difference in three or four weeks."

Street recorded four saves in his first four opportunities this season, before he was placed on the 15-day disabled list on May 5.

Street said the most difficult part of the process is the helpless feeling he has watching his team in action.

"That's the worst part," he noted. "This is baseball season. You want to play. It's not normal not to be playing."

Headley returns to Padres lineup

ST. LOUIS -- San Diego third baseman Chase Headley returned to the starting lineup on Wednesday night after taking a day off to rest a muscle pull in his lower back.

Headley, the iron man of the injury-plagued Padres, started 42 of the first 43 games prior to his much-needed day off.

Manager Bud Black and Headley agreed that it would be best for Headley to take a short rest in order to avoid a bigger problem down the road.

"He's great about letting the player tell him how you feel," Headley said. "I didn't anticipate it being a big deal. It was a good day to get off of it".

Black can be forgiven if he jumps at the slightest hint of a player injury.

The Padres have 13 players on the disabled list, with five out for at least 60 days, including pitcher Cory Luebke, who underwent Tommy John surgery on Wednesday. San Diego has used an NL-high 39 different players this season.

So Black and Headley decided to proceed with extra caution.

"I came in early [Wednesday] and got treatment," Headley said. "It's fine. I would say I'm as 100 percent as you are during the season."

Headley, who leads the team with five homers and 20 RBIs, kept his activity to a minimum on Tuesday and said his back felt much better.

Worth noting

• Triple-A Tucson used a pair of four-run innings to roll past Memphis 9-2 in Pacific Coast League action on Tuesday. Second baseman Jedd Gyorko ripped a three-run homer to highlight an eighth-inning uprising. Matt Clark also homered in the eighth. Memphis is the farm club of St. Louis, which beat the Padres in the first two games of a three-game set in St. Louis.

• Class A Lake Elsinore defeated Modesto 6-0 in California League action on Tuesday. Right-hander Matthew Andriese allowed just two hits over seven innings to improve to 3-3. He struck out five and did not walk a batter. Eddy Rodriguez had a three-run homer to lead an 11-hit attack.

• San Diego right-hander Edinson Volquez ripped a double in the sixth inning of Tuesday's 4-0 loss at St. Louis. It was the first extra base hit for Volquez, who had just one hit in his first 17 at-bats this season.

"Just closed my eyes and swung," he said.

Volquez entered the season with 12 hits in 120 trips to the plate but no extra base hits.