SEATTLE -- Justin Dunn pitched a simulated game on Friday in his bid to return to the Mariners before the end of the season. The right-hander threw about 20 pitches and faced about a half-dozen batters from the mound at T-Mobile Park about four hours before the series opener against the D-backs.

“It went well,” Dunn said. “I wasn't as sharp as I would have hoped to be, but I felt positive when I came off the mound. It was good to feel healthy, so definitely that's the main takeaway for today. That was all I wanted, so hopefully I’ll continue to build off of that and continue along in that direction.”

Dunn has been on the 10-day injured list since June 18 with right shoulder inflammation. He seemed close to a return multiple times, but he had setbacks each time.

Seattle manager Scott Servais said he would need to see how Dunn recovers from the workout before setting a timeline for a possible return. The hope is that Dunn might be able to return in late September or in the postseason (should the Mariners reach it). However, it’s too late for him to return to the starting rotation.

“It would be more of, ‘Can you help us in the bullpen?’" Servais said. "You know, go out and be able to throw 30, 35 pitches, something like that."

Dunn, who went 1-3 with a 3.75 ERA and 49 strikeouts in 50 1/3 innings in 11 starts prior to the injury, would like any chance to help out.

“I’m never going to turn the ball down, and that's what I want to do -- keep this going in the right direction and help this club out,” Dunn said.

Dunn said he wasn’t sure what caused the inflammation, a problem he’s experienced before but not at such length. He said there doesn’t appear to be anything wrong structurally, but the injury has tested his patience.

“Whenever I would try to step on the gas a little bit, it would just say, 'Slow down, I'm not ready,'” Dunn said. “We’re finally starting to find a little formula that's working, so hopefully we keep building off of it.”

Honoring heroes
The Mariners are honoring members of the military and first responders in a pair of pregame ceremonies this weekend. On Friday, members of each of the six branches of the military threw out a first pitch, and the team presented an award to the Washington National Guard for its dedication to serving communities in need.

The Mariners will honor first responders on Saturday, exactly 20 years after the 9/11 terrorist attacks, with more than 80 invited to participate in a ceremony.