Bradenton was the team to watch in the minors at the start of the 2017 season. They had six of the top ten prospects in the system on their Opening Day roster, three in the starting rotation and three in the infield. As you will see in the recaps below, things didn't go exactly as planned. Four of those top six players missed time with injuries and two of them saw their stock drop. Fortunately for the Marauders, they had some other prospects take a step forward. Half of the top ten prospects below ended their season in Altoona, as well as some players who just missed the top ten. It was a solid overall season for prospects progress. Here is our end of the year rundown of the best prospects at the level.

TOP 10 BRADENTON MARAUDERS PROSPECTS

The cutoff for eligibility on this list was 140 at-bats, 40 innings pitched, or 20 relief appearances. That left off Stephen Alemais and Jacob Brentz, as well as Geoff Hartlieb, who made the West Virginia top 10 list. Just like the lower levels, these players are still graded mostly based on projection than actual results, although this is the level where you want to start seeing those results, especially for college drafted players.

1. Mitch Keller, RHP - Keller didn't have the easiest time this year with Bradenton, but by the middle of the season, he established himself as the top prospect in the system. He was coming off a breakout year with West Virginia, one that ended with him throwing eight shutout innings in the playoffs for the Marauders. He had some issues early this season, though he was focusing on throwing his changeup and some of the early damage was off of that pitch. By the end of the season, Keller had a new changeup grip and was seeing strong results with the pitch. That's important that he adds that pitch to his fastball, which touched 100 MPH this season, and his plus curveball, giving him a third look against the better hitters he will see at the upper levels.

Keller missed a month this season with a back injury, and also left three of his starts early for three different reasons. He was still able to put together a 3.03 ERA over 116 innings, with a 1.00 WHIP, 116 strikeouts and a .202 BAA. He then made two strong starts in the playoffs for Altoona. His time in Bradenton got him named as the top pitching prospect in the Florida State League by Baseball America. Keller is on his way to becoming a top of the rotation pitcher for the Pirates. He will open next season with Altoona and a mid-season promotion to Indianapolis is very likely if the results continue. In fact, there is a possibility he could finish the year in Pittsburgh. The first step though, will be continuing to learn how to pitch to upper level hitters and working on his changeup. Keller is currently in the Arizona Fall League working on his pitches and adding to his innings total, making up for some lost innings during the season.

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