Washington Nationals right-hander John Patterson, out for nearly two months with a slow-to-heal nerve injury in his right elbow, is seeking treatment on his own in Toronto that apparently isn't approved in the United States.

After visiting four different doctors in Missouri, Texas and California last week — a trip Patterson himself arranged to learn what is causing the problem — Patterson will undergo a series of injections in Canada, according to the Nationals.

Asked why his opening-day starter is going out of the country for medical treatment, Nationals manager Manny Acta said Saturday, "It's because that treatment is not approved here in the States yet."

Patterson and his agent made the decision to seek the unspecified treatment. The team would not elaborate on what type of injections the right-hander would receive or why he couldn't get them from a team physician or another doctor in the United States.

"The treatment is based on shots, injections," Acta said.

Giants activate Lewis, designate Figueroa: The San Francisco Giants activated outfielder Fred Lewis from the 15-day disabled list, clearing roster room by designating infielder Luis Figueroa for assignment.

Lewis played in seven games for Triple-A Fresno in a rehab assignment as he recovered from a strained a muscle in his right side — and his numbers there were too hard to ignore. Lewis batted 13 for 34 (.382) with two home runs, 12 RBIs, a triple and a double.

Orioles put Trachsel on disabled list: Baltimore Orioles right-hander Steve Trachsel was placed on the 15-day disabled list, less than 24 hours after he struggled in his shortest outing in four years.

Trachsel has a strained muscle below his lower back. He could miss only one start, because part of his stint on the DL will come during the All-Star break.

Cubs recall Cherry, option Petrick: The Chicago Cubs recalled right-hander Rocky Cherry from Triple-A Iowa and optioned right-hander Billy Petrick to the same club.

Cherry will be in his second stint with the Cubs this season. He was 1-1 with a 2.89 ERA in eight games before being sent to Iowa on May 15.

Pirates' Bay sits: Pirates left fielder Jason Bay, stuck in a monthlong slump, didn't start Saturday night for the first time this season.

Bay, the only player to appear in Pittsburgh's first 79 games, was hitting .314 at the start of June but was down to .266 by Saturday. He has homered only once in 19 games and was 13 for 86 (.151) in his 23 most recent starts.