Detroit Tigers right-hander Jordan Zimmermann is expected to be sidelined for up to a month because of a sprained ulnar collateral ligament in his pitching elbow.

Tigers head athletic trainer Doug Teter said Friday that Zimmermann won't be allowed to throw for five to seven days. Zimmermann had an MRI in Chicago on Friday that revealed "some damage to the ligament itself," Teter said.

Zimmermann left Thursday night's game in Boston before the bottom of the fourth inning with elbow discomfort and was put on the 10-day injured list Friday. The 32-year-old allowed five runs on five hits and three walks as he lost his fourth straight decision, dropping to 0-4 with a 5.93 ERA in six starts. He has a 10.26 ERA in his last four appearances.

Santana designated for assignment

The Chicago White Sox designated struggling right-hander Ervin Santana for assignment and inserted lefty Manny Bañuelos in his rotation spot.

Santana, a two-time All-Star, was 0-2 with a 9.45 ERA in three starts after his contract was selected from Triple-A Charlotte on April 9. The White Sox signed him to a minor-league deal in February that called for a $4.3 million salary while in the major leagues. A finger injury, followed by surgery, limited Santana to five appearances with Minnesota last season.

Bobby Cox remains hospitalized

Hall of Fame manager Bobby Cox remains hospitalized after a stroke this month.

People familiar with the situation say the former Atlanta Braves skipper has resumed walking and has regained feeling in his right side since he fell ill on April 3. But the people say Cox, 77, has yet to regain speech.

Phillies, Rockies make trade

The Philadelphia Phillies acquired infielder Hunter Stovall from the Colorado Rockies for left-hander James Pazos.

Pazos was obtained from Seattle in December as part of the trade that sent infielder Jean Segura to Philadelphia. Pazos, 27, was 0-1 with a 6.14 ERA in seven games for Triple-A Lehigh Valley. He is 9-6 with a 3.54 ERA in four seasons with the New York Yankees and Mariners.

A 21st-round pick by Colorado in last year's amateur draft, the 22-year-old Stovall was batting .281 with a .414 on-base percentage in 18 games this season for the Rockies' Class A Asheville farm team.

Wainwright adopts baby

St. Louis Cardinals starter Adam Wainwright has added a fifth child.

The St. Louis Post-Dispatch reports that he and his wife, Jenny, learned Thursday that their adoption of 2-month-old Caleb had been approved. He says his "eyes welled up all over again" when he heard the news.

The couple and their four daughters have been caring for Caleb since birth.