Tarheel Trajectories: Dustin Ackley and Kyle Seager moving in very different directions

In June of 2009, the Mariners took Tarheels standout Dustin Ackley with the second overall pick, second only because there was some guy named Stephen Strasburg in the draft that year. Two rounds later, the M’s gobbled up Ackley’s teammate, Kyle Seager. Though Seager was later regarded pretty highly—ranked by Baseball America as Seattle’s ninth-best prospect in 2011—it was Ackley that was considered the future, it was Ackley that was called up first in 2011, and it was Ackley that put together a rookie-of-the-year run.

Fast forward to this week, and we all know what’s happening. Ackley’s struggles have landed him in Tacoma, while Seager is considered the Mariners’ most valuable position player for the second consecutive season. Their paths have not been determined, but this is a clear lesson about the difficulty of projecting players (and the importance of having a wealth of prospects with which to experiment). Here’s a graph of each player’s month-by-month production since July 2011, as measured by weighted Runs Created (wRC).

Beginning in July of 2011, you can see that in terms of hitting, Seager was never that far behind Ackley. During that first July, Seager stepped into the box just 25 times, but he quickly got going in August. And since May of 2012, Seager has out-hit Ackley during every month. Another way to view their paths is by cumulative runs created.

I removed Ackley’s June of 2011 for a more fair comparison. Ackley got a head start in 2011, especially thanks to Seager’s short July, but Seager began catching up in May of 2012. By the end of the 2012 season, Seager had passed Ackley in terms of cumulative runs created. I guess I was just a little surprised that Seager kept Ackley in his sights early on. I almost forgot Seager even played in 2011, though in my defense, that was a pretty forgettable season.

These graphs only focused on the players’ hitting values, not baserunning, defense, or positional value. Ackley has been sent down for his inability to hit. But the good news is that Ackley is above-average when it comes to baserunning and fielding, that coming from a position that doesn’t often yield much offense. He doesn’t have to turn his hitting value around too much to become a contributing member of the Seattle Mariners again.

The rest-of-season ZiPS projections currently forecast Seager and Ackley as the two most valuable Mariners. Their paths have wound around in an impossible-to-predict fashion, but hopefully with a little help in Tacoma, Ackley can make that ZiPS projection turn out.