Washington Nationals manager Davey Johnson says ace pitcher Stephen Strasburg has “probably” two or three starts remaining before the ace is shut down for the season.

Johnson said Thursday he delivered the news to Strasburg on the plane ride home from Wednesday’s win over the Miami Marlins. Johnson says he has a “pretty firm plan” for Strasburg, but it’s based on how many innings the right-hander pitches in his next starts.

Strasburg is 15-6 and has thrown 150? innings. The Nationals have not announced the innings limit they’ve imposed on him in his first full season since undergoing Tommy John elbow surgery.

Barring a rainout or other change in the rotation, Strasburg’s final start appears set for either Sept. 7 against. Miami or Sept. 12 at the New York Mets.

Collarbone injury sidelines Span

The Minnesota Twins placed center fielder Denard Span on the 15-day disabled list with an injured collarbone.

Span strained the right side of his collarbone while diving to make a catch against Tampa Bay on Aug. 12. He has missed 13 of the 17 games since the injury, with Ben Revere taking over the bulk of the work in center. The move is retroactive to Tuesday.

Span is hitting .286 with three homers and 35 RBI this season.

The Twins say they will announce a corresponding roster move when they arrive in Kansas City today.

Span says he was surprised by the decision. But he also says he knows it’s “not fair to the team” to keep coming in and scratching himself from the lineup.

White Sox bring up infielder

The Chicago White Sox purchased the contract of infielder Jose Lopez from Triple-A Charlotte on Thursday and placed backup catcher Tyler Flowers on the paternity leave list.

Lopez was signed to a minor-league contract by Chicago on Aug. 14 after being designated for assignment by the Indians. The 2006 AL All-Star is a .262 career hitter over nine seasons.

Chicago also transferred right-hander Brian Bruney to the 60-day disabled list and released minor league right-hander Gregory Infante, who spent more than seven seasons in the organization but appeared in only five games with the White Sox (in 2010).

Bruney underwent season-ending surgery on Aug. 13 to repair the labrum in his left hip.

Rodriguez to play in games

Injured New York Yankees third baseman Alex Rodriguez is set to play in the minor leagues tonight.

The 37-year-old star has been out for more than a month because of a broken left hand. He is scheduled to play for Class A Tampa at Lakeland in the Florida State League.

Rodriguez is hitting .276 with 15 home runs and 44 RBI for the Yankees.

Yankees extend Trenton affiliation

The New York Yankees are extending their affiliation with the Class AA Trenton Thunder for another eight years.

The teams made the announcement Thursday at the ballpark in New Jersey’s capital city where the Thunder play.

Trenton has been the Yankees’ Class AA affiliate since 2003, after eight years as a farm team for the Boston Red Sox. Their current agreement with the Yankees has two years left on it.

The deal will extend the affiliation through 2022.

Halman’s brother acquitted

A Dutch court in Amsterdam acquitted the brother of Seattle Mariners outfielder Greg Halman of stabbing the baseball star to death last year, saying he was temporarily insane at the time.

Rotterdam District said Jason Halman “was in a state of psychosis at the time of the stabbing” and therefore cannot be held accountable for his actions.