After four years with the Boston Red Sox, veteran reliever Koji Uehara has found a new home with the Chicago Cubs

ESPN.com’s Jesse Rogers reported Wednesday that Uehara inked a one-year, $6 million deal with the defending World Series champs, and the Cubs later announced the news. 

Uehara is one of the most interesting relievers in Major League Baseball. He has performed at a high level for nearly a decade despite having a fastball that FanGraphs‘ stats show has never averaged more than 89.2 mph and dipped to a career-low 86.7 mph in 2016

The key to Uehara’s success is his split-finger fastball that drops off the table when he’s at his best, as Tim Britton of the Providence Journal wrote in 2014: “It was also the most effective his splitter has ever been, as opponents hit a beggarly .096 off the pitch in 2013. It induced a career-high whiff rate of 28 percent.”

Turning 41 last April, Uehara is starting to show signs he lacks the same type of dominance with that splitter. His 1.5 home runs allowed per nine innings tied the worst mark of his career (2011), per Baseball-Reference.com.

The veteran also posted his highest ERA since 2009 with a 3.45 mark last season, but he still baffled hitters overall with his seventh consecutive season posting a WHIP lower than 1.00 and more than 10 strikeouts per nine innings, so the sky is hardly falling for the right-hander. 

The concern for Uehara is there’s such a small margin for error with his declining fastball velocity that at some point hitters will be able to tee off on the pitch, negating the effectiveness of his splitter, as right-handed hitters gave him fits last season. 

Until that point comes, though, Uehara is still one of the most consistent relievers in baseball and a terrific value because his age didn’t force the Cubs to break the bank.

While Chicago was unable to keep closer Aroldis Chapman in free agency, it acquired Wade Davis via trade and now boasts a potentially dominant late-inning trio with Uehara joining both Davis and Hector Rondon.

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