Michael Almanzar might be the best first base prospect in the Boston Red Sox system. Currently, he is more of a third baseman, but based on organizational depth and his skill set, he projects best at first base.
Defensively, he is poor. He has sloppy footwork, an inaccurate arm, and limited range. He has not looked comfortable at first base, but it is really the only position he could make it to the big leagues.
If athleticism and defense are his negatives, his positive is power, along with some more power. His biggest home run season came in 2013, launching 16 for AA Portland, and it was also his second best season in terms of hitting for average. He still struggles with pitch recognition, but has made great strides in his six seasons in the Red Sox organization. Despite being a power hitter with little athleticism in the field, Almanzar is surprisingly effective at stealing bases; he swiped 13 bags and was only caught three times.
Almanzar had an incredible start to the season, 11 of his home runs coming by June 5, but sputtered down the stretch, which might be a good thing. He is Rule 5 eligible, and had his hot start continued through the entire season, he would certainly be at risk of being selected, and would likely have to be added to the Red Sox 40-man roster.
Assuming Almanzar is still property of the Red Sox come spring, he will probably start next season at AA again, but could be a quick promotion to the Pawtucket Red Sox, and could offer a power bat off the bench late next year in the big leagues.