Veteran free agent starter Cliff Lee has been cleared by doctors to begin working his way back to the hill, Jon Heyman of CBSSports.com reports on Twitter. Lee has already begun throwing and intends to pitch in 2016 so long as he can find the right opportunity.

There figures to be no shortage of interest in the one-time ace. Clubs pay good money for the right to take risks on injured players all the time, but rarely is there as much upside as comes with Lee.

True, Lee is already 37 years of age and is looking to return after a lengthy rehab from a partially torn flexor tendon. But he’s also thrown at an exceedingly high level as recently as 2014. Though he only put up a 3.65 earned run average in his 81 1/3 innings that year, Lee carried a 6.00 K:BB rate and drew ratings from metrics that valued his effort in the 3.00 earned-per-nine range.

Of course, Lee has also shown much more prior to that season. He racked up over 220 frames per season over 2011 through 2013, working to a cumulative 2.80 ERA in that span while striking out a batter per inning and walking less than one-and-a-half per nine.

It goes without saying that Lee’s past success guarantees nothing moving forward. He might re-injure his arm. Or he might have reduced velocity, movement, and/or command. But even a lesser version of Lee would likely be a productive big league asset, and there’s hope of much more. Assuming he continues on track to throw in 2016, Lee will be a fascinating player to watch on the market.