Chase Field’s standing as one of baseball’s most hitter-friendly ballparks is subject to change. The Diamondbacks officially will unveil a humidor for 2018, General Manager Mike Hazen said. The humidor – a climate-controlled chamber in which baseballs are stored – could drastically impact how hard balls are hit and, as a result, how far they travel. It is expected to lead to a decline – perhaps a significant one – in home runs. The contraption has been a long time coming in Arizona. The club has been kicking around the idea of implementing a humidor off and on since 2010. The team expected to begin using one midway through last season, but those plans were put on hold due to difficulty maintaining calibrations. The club has continued to work its way through the testing process throughout this offseason. The Diamondbacks will become the second team to employ a humidor, following in the footsteps of the division-rival Colorado Rockies, who saw an immediate decline in home runs after beginning to use theirs in 2002. When a ball is stored in a humidor, it absorbs water, decreasing its “coefficient of restitution,” i.e., its bounciness. The lower a ball’s coefficient of restitution, the lower its exit velocity will be. The humidor is also expected to have a more anecdotal benefit for pitchers, who say dry baseballs are harder to grip.