As you've undoubtedly heard by now, Dante Bichette Jr. has been promoted to Double-A Trenton where he will be the team's everyday third baseman for the remainder of the season. It's great to see him rebound this year after two very bad seasons in Low-A Charleston, and while it's good to see him move up a level, the move really benefits fellow third base prospect Eric Jagielo more.
After two seasons where Bichette hit a combined .232/.308/.331, his prospect status didn't just come into doubt, it essentially disappeared. His ability to stay at the position was already in doubt, but his inability to hit made it all a moot point anyway as it looked like he was destined to fall into the minor league abyss. With the seeming bust of their third base prospect, the Yankees drafted Eric Jagielo in 2013 and gave him the keys to the third base castle. No matter where he was assigned, he wouldn't have to worry about any other third baseman because he was going to be top dog wherever he went.
Then in 2014, the Yankees did something odd; despite his struggles, they let Bichette move up to High-A Tampa while also aggressively pushing Jagielo to the same team. Still, it didn't seem like too much of a problem because Jagielo would start 70% of the time at third and Bichette would be the DH. Of course, no one was planning on Jagielo getting hurt and Bichette actually turning into a halfway decent hitter. From the time Jagielo went on the disabled list at the end of May to when he returned in mid-July, Bichette, now the everyday third baseman, hit a surprising .303/.380/.444, thanks to a completely refined swing. While it was unexpected, it didn't exactly get in the way of Jagielo's development because he wasn't even there. When Jagielo came back, Bichette was hitting well and not exactly deserving of being pushed back to his old role.
Since coming off the DL, Jagielo's time at third base has gone down to 63%, despite him hitting .250/.333/.426 and Bichette coming down to earth with a .208/.266/.347 batting line. The better prospect deserved more time at his position, however, Bichette had built up enough goodwill to keep his bat at the hot corner. If it looked like Jagielo would be getting less playing time at his position, the Yankees should have acted immediately and had Bichette moved somewhere else. Since Jagielo had already been assigned aggressively to Tampa, it made more sense to push Bichette up a level and get him out of there to let Jagielo have more playing time.
Neither is considered to be very good defensive third baseman, so it's absolutely for the best that both get their own assignment where they don't have to share the position with anyone. It's nice to see Bichette move up after all his struggles, but his promotion is more about getting him out of the way than rewarding his performance, which has leveled off quite a bit. As the better prospect, Jagielo should have the position all to himself. He should be the team's priority and no way was he about to get pushed up to Trenton so soon in his career and after coming back from injury. Moving Bichette is certainly good for him, but it's better for Jagielo.