After trading for outfielder Matt Diaz on Wednesday morning, the Braves continued to pursue one more roster piece before the midnight deadline to add players to their system in time to be eligible for the postseason roster.

The only significant piece left on their wish list was a backup middle infielder. The Braves were in on discussions early in the day with the Dodgers about infielder Jamey Carroll, but the Dodgers either were reluctant to trade him or were asking too much.

The Braves upgraded center field and the leadoff spot at the non-waiver trade deadline July 31 with the acquisition of Michael Bourn. They took care of their right-handed relief needs by calling up Arodys Vizcaino and are poised to bring back Peter Moylan from the disabled list.

The Braves wanted to upgrade the backup shortstop position with a more consistent offensive producer — Julio Lugo is hitting .136 (6-for-44) in limited action.

“It’s not essential,” general manager Frank Wren said of a final move. “It’s not something that we have to do. Even if it’s in small increments, you’re trying to improve the club in every area you can. That’s what this time of year calls for.”

Sherrill to DL

To make room for Diaz on the 25-man roster, the Braves placed reliever George Sherrill on the 15-day disabled list with elbow inflammation. Manager Fredi Gonzalez said Sherrill has been nursing the injury for several weeks.

Sherrill has pitched only 1 1/3 innings in the past 2 1/2 weeks. He hasn’t pitched since Friday in New York, so he’ll be eligible to return Sept. 11 in St. Louis.

“He just needs to rest it and get over it so we can have him the second half of September and hopefully in the postseason,” Wren said.

Salazar to join call-ups

Lynchburg manager Luis Salazar will be among the minor league coaches the Braves reward with a September call-up. He gets the sentimental vote, after all he has been through since losing his left eye in a spring training accident, but that’s not why the decision was made.

“When we looked at the guys that who were deserving, he was one of them,” Wren said. “He’s done a terrific job with that team.”

Salazar, who was hit by a Brian McCann foul ball in spring training, underwent multiple surgeries, but joined Single-A Lynchburg by its home opener and has managed the Hillcats throughout the season. They were 58-74 entering Wednesday, but he has guided the development of multiple prospects from the 2010 draft.

Salazar will join the Braves after Lynchburg’s season ends Sept. 5 and remain with the club for a week. Typically the Braves rotate minor league coaches for one week each in September.

Moylan update

Moylan passed the biggest test of his minor league rehabilitation assignment Wednesday when he completed his first back-to-back appearance for Triple-A Gwinnett. Moylan pitched a scoreless inning in Norfolk, allowing one walk, one night after striking out all three batters he faced Tuesday night in Durham.

Moylan is scheduled to pitch one more time for Gwinnett on Saturday and if all goes well, he’ll return from the DL when the Braves open a series in Philadelphia Monday.

Moylan underwent surgery for a herniated disc May 17. He has maintained that his back has given him no issues throughout his recovery, and he has the numbers to prove it. Moylan has thrown six scoreless innings with five walks and seven strikeouts, allowing only two hits.