Tigers lefty Matthew Boyd is being evaluated after exiting tonight’s start during the third inning with what the team is terming “left arm discomfort,” per a club announcement. Boyd signaled into the dugout for a trainer to come out after 2 1/3 innings of work against the Royals tonight (video link).

While the hope is that he’ll avoid any notable injury, the departure of such an obvious trade candidate this time of year is plenty notable. Boyd has pitched quite well thus far in 2021, bouncing back from an awful 2020 season to post a 3.44 ERA through his first 70 2/3 innings. His 19.6 percent strikeout rate is his lowest since 2017, but Boyd’s 6.4 percent walk rate is also the second-best mark of his career (narrowly trailing a 6.3 percent mark from 2019).

Boyd, 30, was a popular target on the trade market a couple years back, but the Tigers had more than three years of control over him at that point and opted to hold on with the hope of extracting a better offer at some point down the road. Unfortunately, Boyd took a step back in 2019 and then had the worst year of his career in 2020, so that opportunity has yet to present itself.

At this point, the Tigers control Boyd for just one more year after the current season, making him perhaps one of the likeliest players in all of baseball to be dealt — assuming he’s healthy. He’s earning a reasonable $6.5MM salary in 2021 and has been more effective than ever before against right-handed opponents, in part due to an increase in the use of a changeup that has generally befuddled opposite-handed opponents.

Opposing hitters are batting just .224/.246/.343 in the 69 plate appearances Boyd has finished off with a changeup, and the pitch itself has generated a 29 percent whiff rate, per Statcast. Entering play tonight, Boyd had thrown just two changeups to lefties all season but 244 to right-handers; he threw just 187 changeups in a similar workload last season and only 182 over the course of 32 starts in 2019.

Even if the discomfort proves minor enough that Boyd doesn’t miss an outing, his performance and health from this point forth will obviously be all the more important to monitor for those who closely follow the trade market. There’s still a bit more than six weeks to go until the July 30 deadline, so if Boyd shakes off the current ailment and continues at his previous pace in the weeks leading up to the deadline, this will be a quickly forgotten blip on the radar. If he requires a lengthy absence or sees an immediate dip in his results in the coming weeks, there will be obvious implications for the Tigers that extend well beyond their 2021 win-loss record.