To keep us entertained during this lull of baseball activity, Seattle Mariners general manager Jerry Dipoto keeps making trades — and he acquired an interesting bullpen arm in Shae Simmons on Wednesday.

In the trade, Seattle dealt one of its top prospects, Luiz Gohara, to Atlanta for center fielder Mallex Smith and Simmons.

Simmons doesn’t headline the trade, but he’s an intriguing component of it at a time when the industry is paying premium prices for relief help.

A 22nd-round pick by the Braves in 2012 out of Southeast Missouri State, Simmons rose from obscurity to become the Braves’ second-best prospect by WAR prior to the 2015 season.

Prior to that 2015, former FanGraphs prospect analyst Kiley McDaniel ranked Simmons as the Braves’ No. 15 prospect and was given a “poor man’s Craig Kimbrel” comp on Simmons.

Wrote McDaniel:

“Simmons shot through the upper levels in 2014 and posted 21.2 quality innings in the big leagues on the strength of his 93-96 mph fastball that hits 97 mph. Simmons also has a 55 curveball and 50 splitter, but they can waver at times when his delivery and command get out of whack. There’s setup potential here and Simmons may get there early in 2015.”

Did “poor man’s Kimbrel” grab your attention?

Simmons employed his fastball-slider combo to strikeout 12.9 batters per nine innings over the course of his four years in the minors, allowing just 76 hits in 120 career minor-league innings en route to a sparkling 1.80 ERA. (Kimbrel averaged 14.4 strikeouts per nine in the Braves system, posting a 1.85 ERA and 75 hits allowed in 151 innings.)

All those nice things were said and written of Simmons in January of 2015.

In February of 2015, however, Simmons had Tommy John surgery.

For many pitchers, TJ is simply a bump in the road thanks to modern medicine and strength and conditioning programs. Fellow right-handed reliever Bruce Rondon had Tommy John a spring prior to Simmons, and he was as good as he had ever been when he returned to the Tigers late last summer, striking out 11.8 and walking 3.0 batters per nine — the latter figure representing an improvement for Rondon — in 26.2 second-half innings. Rondon pitched last season at 25; Simmons is entering his age-26 season.

Daniel Hudson had a second Tommy John surgery at age 26 in the spring of 2013, and he’s posted FIPs of 3.49 and 3.81, respectively, in 2015 and 2016. In a market paying a premium for relief pitching, the small-market Pirates signed Hudson to a two-year, $11 million deal last month.

Hunter Strickland had Tommy John at 24 in 2013 and has been a quality reliever for the Giants since returning.

Of course, not every reliever returns successfully. Bobby Parnell has struggled mightily since his spring 2014 procedure, though Parnell had the surgery as a 30-year-old. Jonny Venters could never catch a break. And it’s important to note: a return from Tommy John surgery is not the same as a successful return. Perhaps success rates have been overstated, as Jon Rogele’s research for the Hardball Times indicates.

In trading for a player with a limited track record coming off surgery, risk factors increase. But Simmons is still in his mid-20s and the early signs following his return have been encouraging.

We have two small samples of Simmons’ work at the major-league level.

In 21 innings with the Braves in 2014, Simmons recorded an average fastball velocity of 94.9 mph, which he threw nearly 70% of the time. He also featured a breaking ball (which is classified alternately as a curveball and slider) and rare split-finger fastball.

In a seven-game major league sample after returning from surgery last season, Simmons’ fastball velocity was up a full mph to 95.9.

See Simmons’ fastball in action here:

According to our PITCHf/x data, he threw his breaking pitch 32% of the time last summer in his brief showing with the Braves.

This is evidence of his lone swinging strikeout with the pitch as he back-footed a breaking ball against left-handed hitting Danny Espinosa last September:

The Mariners hope he can hone his delivery and command, which have been inconsistent. He walked more than six per nine during two minor-league rehab stops last season. But he’s limited opponents to 11 walks in his brief 28 innings of major-league work to date, and his stuff appears to be intact, if not improved, following his injury.

Dipoto offered some thoughts on the trade to the Seattle Times. “Shae has had success pitching at the back end of games in the minors and has shown strikeout ability at all levels,” Dipoto said.

Dave Cameron wrote earlier this week about how the Mariners are perhaps trying to model their outfield defense after the Royals. And every team is trying to assemble a Royals-like bullpen. So perhaps trying to identify a future quality back-end arm before it becomes a present quality back-end arm is a smart play in a market that will pay a premium for it.