DETROIT — Mariners manager Don Wakamatsu doesn’t want to hide anything, nor does he want a decision hanging over his head, so before Tuesday’s game with the Tigers, he said the team would announce on Wednesday which pitcher would be joining the rotation for the upcoming homestand against Cleveland.

Because of the All-Star break and off-days, Seattle has used only four starters on this seven-game road trip.

But the need for an additional starter will arise this weekend.

“We’re still talking about the fifth starter,” Wakamatsu said. “We haven’t made that decision yet. We’ll make that probably by (today).”

The three most likely candidates — Jason Vargas, Ryan Rowland-Smith and Brandon Morrow — are all pitching in Triple-A.

The original plan was to have one of them start Saturday. But Wakamatsu said that plan could be tweaked.

“We have some options and maybe we’d give (Erik) Bedard one extra day and maybe go (with the fifth starter) on the 24th,” Wakamatsu said. “We kept talking about the 25th, but we might do it on the 24th.”

Of course, after Garrett Olson’s start Tuesday — giving up seven earned runs in 1 1/3 innings — Wakamatsu could be calling up two starters.

The candidates’ schedules don’t lend much insight into who the likely call-up is.

Rowland-Smith has pitched the best of the three recently. He’s won his last three starts, pitching 21 innings, allowing four runs and striking 20 hitters.

Vargas could be a candidate, but he pitched Monday for the Tacoma Rainiers, so starting Friday wouldn’t give him enough rest, though he might have an outside shot at a Saturday start.

Vargas was decent in his start with the Rainiers, throwing six innings, giving up three runs and nine hits while walking three and striking out three.

“They weren’t great,” Wakamatsu said of the reports on Vargas. “I think that the command was the biggest issue. You end up having a couple good innings, and I think the fourth is where he ended up giving up two runs on three hits and a walk. Not exactly what we were looking for.”

The best timing would favor Brandon Morrow, who is slated to start Friday for the Rainiers. But his first outing with Tacoma since he was sent down wasn’t great. He allowed four runs in the first inning, and was bothered by control issues.

“The things that we talked about him working on, I didn’t think we accomplished,” Wakamatsu said. “He walked the first hitter on four pitches, so the command overall was not what we were looking for from him. Second, with his secondary pitches — we talked about going a little bit hard and soft, and we didn’t see that also. When he tried to throw his curveball, he yanked it out of the zone. Again, we just keep going back and try to reiterate what’s going to make these guys successful at the major league level.”

With Olson’s struggles and Morrow’s inconsistency, the odds are tipping in favor of Vargas or Rowland-Smith.

Sweeney activated

In a minor roster move, designated hitter Mike Sweeney was activated off the disabled list and utility infielder Josh Wilson was designated for assignment. The Mariners have 10 days to either trade, release or re-assign Wilson, providing he clears waivers.

Sweeney seemed genuinely upset about taking Wilson’s place.

“It breaks my heart that a guy like Josh Wilson has to get sent out,” Sweeney said.

Wilson appeared in six games and had two at-bats since the Mariners claimed him off waivers June 19.

Sweeney went on the disabled list for back spasms July 7, retroactive to July 6. But he said he didn’t need 15 days to heal.

“I told Jack (Zduriencik) and Wak that I’d only need three days,” Sweeney said. “I know my body pretty well, especially with back and knee pain. I know how long it’s going to keep me out. They told me after a few days they needed a spot for Bedard, and I told them, ’whatever is best for the team, is best for me. If this is something you need to do, do it.”’

As for staying ready, Sweeney has been taking batting practice and been very active the last seven days. He isn’t concerned about being rusty when he comes back.

“I have a routine that gets me ready to play, and if I’m in the lineup I’ll be ready to go,” he said.