Seattle Mariners right-hander Hisashi Iwakuma, who was placed on the disabled list last week due to right shoulder inflammation, said Monday he expects to return to the mound before the All-Star break.

The 36-year-old told reporters in Seattle that he had been experiencing pain in his right shoulder for some time and the recovery period will give him a much-needed break, insisting the injury is not serious.

"I've been told four to six weeks so I'll adjust my condition with that in mind. I should be back (in the first half of the season)," said Iwakuma, who underwent medical tests on Friday.

Iwakuma revealed that he also had tests on his bruised left knee "just to be sure" after he was hit by a line drive against the Los Angeles Angels on May 3.

He said he is staying away from throwing at right now but plans on rejoining the Mariners' rotation before All-Star week, which will be from July 7-11.

"The discomfort is something I've had for a while and it's not a new injury. I'm not worried and don't think there will be a problem if I give it rest," said Iwakuma.

"For the past five to 10 years I've been feeling (pain) in every game."

Iwakuma is 0-2 with a 4.35 ERA in six starts this season.