Twins catcher Joe Mauer probably won't be ready to come off the 15-day disabled list Thursday, the first day he's eligible to return, General Manager Bill Smith said today.

Smith doesn't have a timetable for Mauer's return but said the catcher lost about one week of recovery time with a viral infection.

Mauer, 28, was placed on the DL with bilateral leg weakness. Smith said Mauer is past the viral infection and working hard to rebuild leg strength.

Smith said he's not sure if Mauer will be heading on a minor-league rehab assignment, but Manager Ron Gardenhire has said that's a good possibility.

Mauer, who last played April 12, is batting .235 with a .289 on-base percentage, no homers and four RBI.

OTHER UPDATES

* Smith said Tsuyoshi Nishioka (broken left fibula) "is on schedule, if not ahead of schedule." Nishioka played some catch Sunday and has done some work on both an underwater treadmill and a regular (dry-land) treadmill. The injury happened April 7, and the Twins said it would take the bone 4-6 weeks to heal.

* The Twins will have a decision to make with Kevin Slowey, who is scheduled to throw 45 pitches in an extended spring training start Wednesday. If they want him to return in short relief, he could be ready Thursday, but if they want to stretch him out for a long-relief or starting role, he'll need more time in Fort Myers, Fla.

* Smith said the reason Tuesday's postponement was rescheduled for Thursday, instead of July when the Rays return, was that both teams are rested and ready this week. Neither team has an off day in July outside the All-Star break, and the Twins are trying to schedule a doubleheader after the break against Cleveland, making up for Friday's postponement.