Oakland Athletics reliever Sean Doolittle took another step forward in his efforts to come back from a left shoulder strain that has limited him to just one inning of work in 2015.

On Tuesday, Doolittle began his rehab stint with the A's Triple-A affiliate Nashville Sounds, and by all accounts things went well. Of particular note, as reported by MLB.com's Jane Lee, was the fact that Doolittle's velocity was up. This is key, considering the one inning he threw back in May was characterized by a significantly diminished fastball.

Lee mentions that Doolittle reached 92 mph on the radar gun, an increase from the 89 mph he threw during that outing in May.

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Said manager Bob Melvin to Lee regarding Doolittle's progress: "I know he felt good about it, and we thought we saw better velocity in the simulated game and the bullpens proceeding that,"I know he felt good about it, and we thought we saw better velocity in the simulated game and the bullpens proceeding (sic) that."

Doolittle will pitch on Friday for the Sounds and could be activated from the disabled list while the A's are playing at home next week.

Even though the A's are more or less buried in the standings, having a (hopefully) healthy Doolittle back would be a boost, especially as they look at their 2016 prospects. That Melvin used the phrases 'best he's felt' and 'most comfortable he's felt on the mound' in describing his rehab outing to Lee has to be a good sign, too.

(h/t MLB.com)