PHOENIX -- Padres catcher Yorvit Torrealba was scratched from Tuesday's starting lineup with a stiff back. He was replaced by Nick Hundley, who was slated to bat eighth against D-backs starter Ian Kennedy.

Torrealba, who went 2-for-4 in Monday's 7-2 defeat, tweaked his back while reaching for a missed-location Edward Mujica pitch in the ninth inning.

San Diego skipper Bud Black was not overly concerned; he said it was not a recurring issue for Torrealba, who has started behind the plate 67 times this season.

Luebke to make Major League debut Friday

PHOENIX -- Cory Luebke will make his long-awaited Major League debut on Friday against the Rockies at PETCO Park. San Diego skipper Bud Black announced Luebke's promotion before his club's game on Tuesday in Arizona.

Black said Luebke, one of a handful of players that will officially be called up when rosters expand from 25 to 40 players on Wednesday, will join the rotation with the opportunity to stick. Black added that no decision has been made on who Luebke would replace on the starting staff. Lefty Wade LeBlanc, who had a 6.47 ERA ERA in six August outings, is one candidate.

The left-handed throwing Luebke, the Padres' first-round (63rd overall) selection in the 2007 First-Year Player Draft, is 10-1 with a 2.68 ERA and 88 strikeouts in 114 innings between two Minor League stops this season.

In the interim, given Thursday's off-day, each Padres starter will pitch on seven, not five days, of rest. As a result, Jon Garland will toe the rubber on Saturday and Clayton Richard will throw on Sunday.

Black said the maneuvering allowed each pitcher to take a breather prior to the stretch run. It should benefit young Mat Latos the most, though Black said that if Latos feels fine physically after he hits 180 innings -- the semi-limit Padres' brass previously outlined -- he would still be able to pitch into October. Latos is currently at 149 2/3 innings, and threw a total of 123 between the Minors and Majors last season.

Padres' roster to expand with influx of talent

PHOENIX -- In addition to Cory Luebke, who will be called up to pitch Friday, a handful of other players will join the Padres as rosters are expanded from 25 to 40 players on Wednesday.

Right-handed reliever Ryan Webb, who was on the same flight as Luebke on Tuesday, will join the club on Wednesday. Webb was 3-1 in 40 appearances with the Padres this season before being optioned to Triple-A Portland on Aug. 21.

Also, outfielder Oscar Salazar was already in the visiting clubhouse at Chase Field on Tuesday afternoon. Salazar, who will be activated off of the 15-day disabled list having recovered from his strained Achilles tendon, gives the Padres more outfield depth with Tony Gwynn (fracture in right hand) and utility man Jerry Hairston Jr. (sprained right elbow) currently shelved with their own ailments.

San Diego skipper Bud Black said outfielder Luis Durango was "probable" to rejoin the Padres soon and that a third catcher -- either Dusty Ryan or Chris Stewart at Portland -- could possibly arrive in two to three days.

Worth noting

Arizona Fall League rosters were released on Tuesday, and a contingent of Padres prospects will be competing for the Peoria Saguars. Those prospects indlue pitchers Brad Brach, Steve Garrison, Craig Italiano and catcher Luis Martinez as well as infielders Cole Figueroa and Logan Forsythe. AFL play begins Oct. 12.