Philadelphia Phillies ace Roy Halladay is expected to miss six to eight weeks because of a strained right shoulder, the latest major setback for the five-time National League East champions.

Halladay was put on the 15-day disabled list Tuesday, two days after he was hit hard and pulled from a start in St. Louis after just two innings because of shoulder soreness.

The two-time Cy Young winner will be shut down for a minimum of three weeks, then work toward rejoining the rotation, Phillies Assistant General Manager Scott Proefrock said.

Proefrock said tests done in Philadelphia indicated Halladay doesn’t need surgery to recover and that the injury doesn’t affect his rotator cuff.

“We hate to have him down, but it’s nothing that requires anything other than rest,” Proefrock said.

Weaver, others out with injuries

Los Angeles Angels ace Jered Weaver was placed on the 15-day disabled list with a lower-back injury that likely will force last season’s AL Cy Young runner-up to miss at least two starts. … Washington Nationals infielder Chad Tracy will require surgery for a torn groin muscle and is expected to be sidelined at least six weeks. … The New York Mets put infielder Justin Turner on the 15-day disabled list because of a sprained right ankle and cut right-handed reliever Manny Acosta.

Back in action

All-Star center fielder Matt Kemp was activated from the 15-day disabled list by the Los Angeles Dodgers after missing 13 games because of a left hamstring strain. … The Tampa Bay Rays purchased the contract of designated hitter Hideki Matsui from Triple-A Durham and optioned outfielder Stephen Vogt to Durham. … Right-hander Ryota Igarashi was claimed by the New York Yankees off waivers from the Toronto Blue Jays. … The Pittsburgh Pirates called up infielder Jordy Mercer from Triple-A Indianapolis. … The Blue Jays recalled infielder Mike McCoy from Triple-A Las Vegas and optioned outfielder Eric Thames to the PCL club.

Ordonez decides to retire

Magglio Ordonez, 38, has decided to call it a career. The former Detroit Tigers and Chicago White Sox outfielder plans to announce his retirement Sunday before Detroit plays the New York Yankees.