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After enduring the worst year of his MLB career, Matt Holliday will reportedly reunite with the Colorado Rockies after agreeing to a minor league deal on Saturday with the team that drafted him, according to Fancred's Jon Heyman.

Although he was an All-Star in 2012 and 2015, the 38-year-old's offense has generally trended downward following the 2011 season. He batted .296, slugged .525 and finished with a .912 OPS then, and almost every year since, his OPS fell compared to the year before.

Things reached a nadir for Holliday in 2017. In 105 games for the New York Yankees, he had a .231/.316/.432 slash line along with 19 home runs and 64 RBI. And despite logging the third-fewest plate appearances of his career (427), he struck out his third-most times in a single season (114).

In particular, Holliday struggled when opposing pitchers attacked him with something other than a fastball. According to Brooks Baseball, he had an 8.72 percent whiff rate on fastballs. That number climbed to 18.38 percent for breaking balls and 22.09 percent for off-speed pitches.

Some expected Holliday to have a bounce-back 2017 after he batted .253 on balls in play in 2016, per FanGraphs. Instead, it may be fair to wonder whether the fractured thumb he suffered in August 2016 had had a long-lasting effect on his swing.

In the team's press release announcing his signing, the Yankees noted Holliday had an average exit velocity of 94.7 mph, which was third-best among hitters with at least 100 batted balls in play. According to Baseball Savant, his average exit velocity fell to 89.9 mph in 2017.

No slugger is immune to the aging curve, and the thumb injury may have accelerated his inevitable decline.

Holliday's 19 homers illustrate he still boasts plenty of power. The problem is that power came far more inconsistently than it did when he was in his prime with the Colorado Rockies and St. Louis Cardinals.

In September, NJ Advance Media's Brendan Kuty speculated Holliday wouldn't be back in New York in 2018. In addition to the player's underwhelming offense, Kuty noted he is almost exclusively a designated hitter now since he can't regularly play one of the three outfield positions anymore.

However, Kuty also wrote that Holliday "has been a huge mentor to Aaron Judge, Clint Frazier and likely other hitters we don't know about."

As well as hoping for Holliday to turn things around at the plate in 2018, the Rockies may be counting on him to have a similar impact inside their clubhouse.

Stats are courtesy of Baseball Reference unless otherwise noted.