SEATTLE — Mariners ace Erik Bedard went on the 15-day disabled list Tuesday with inflammation in his left hip, a condition that is improving enough that Seattle expects him to miss just one start.

The move is retroactive to April 9, though Bedard isn’t sure when he might pitch again.

Seattle traded five players to the Baltimore Orioles in February for the 28-year-old Bedard, boosting hopes of a playoff berth this season. He was scratched from a scheduled start Sunday for the second time in eight days.

The left-hander played catch before Tuesday’s game against Kansas City, then emerged from manager John McLaren’s office with a trainer smiling and joking.

“It’s a lot better,” Bedard said, adding when asked if the pain comes and goes that “it’s going now.”

But when asked if he would be able to take his next turn in the rotation Friday at the Los Angeles Angels, Bedard said, “No way.”

Seattle announced an hour later that Bedard was going on the DL. The Mariners will make a corresponding roster move Wednesday.

“We have said consistently that were not going to rush Erik back,” McLaren said. “At this point, we thought it made the most sense to go ahead and place him on the DL. It should not change when he’s available to make his next start, and gives us the ability to add another player in the meantime.”

McLaren said knuckleballer R.A. Dickey, whose last major league start was 24 months ago with Texas, will take Bedard’s start against the Angels. The manager added after Tuesday’s 11-6 win over the Royals that Bedard will then probably be back to take his next turn the day he is eligible to come off the disabled list, April 24. That is the last day of a three-game series with Baltimore.

“I think that’s realistic,” McLaren said.

Bedard set an Orioles record with 221 strikeouts last season despite missing the final month of the season with a strained side muscle. He said he doesn’t know when he can get back on a mound for a bullpen session, let alone a game.

“I think rest is the only thing that helps it right now,” he said.

Bedard isn’t sure if his hip is destined to bother him all season.

“I have no idea,” he said. “My next start, we’ll see. If it still hurts after that, then maybe it will be a long-term thing.”

Bedard said he had hip inflammation in 2000 during his first full professional season in the Orioles’ minor leagues, but not again until he told the Mariners about the pain before his scheduled homecoming start at Baltimore on April 6. Two nights later, at Tampa Bay, Bedard allowed five runs in a laborious six innings but got enough offensive support for his first win with Seattle.

His third missed start this month comes while All-Star closer J.J. Putz continues to make incremental progress toward returning from a ribcage injury that has sidelined him since April 1. Putz will throw off a bullpen mound on Wednesday for the second time this week and may throw in a simulated game before the weekend.

The Mariners still haven’t decided if Putz, who is unlikely to come off the disabled list when he is eligible on Friday, will go to the minor leagues for a rehabilitation assignment before being activated.

McLaren keeps emphasizing patience and caution with Putz, too.

Dickey is a 33-year-old former No. 1 draft choice of the Rangers who arrived Tuesday from Triple-A Tacoma and pitched a perfect ninth inning hours later. It was his first major league appearance since April 6, 2006. He has been with Milwaukee and Minnesota since Texas let him go later that year.

Now he gets his first start in two years.

“It’s a real redemptive game,” Dickey said. “Yeah, it’s been a long time. It will be great. And it will be redemptive.”