Alvarez capped his first season in the Majors by hitting .311 with five homers, 26 RBIs, 10 runs scored and 16 extra-base hits in September. The only NL player with more RBIs last month was Colorado's Troy Tulowitzki, who was named the league's Player of the Month.
During the month, Alvarez enjoyed an 11-game hitting streak, which came to an end on Saturday. He hit .467 with 21 RBIs during that stretch and was also named NL Player of the Week.
"I'm just trying to go out there and compete every day, and not worry too much about the results -- but trust in my process and game plan," Alvarez said at the time. "I believe that more times than not, it will pay off my way."
The rookie third baseman used the strong finish to push his final season batting average to .256. He finished with 16 homers -- a franchise record for a rookie third baseman -- and 64 RBIs. No Major League rookie had more RBIs from June 16 to the end of the season than Alvarez.
"This game has slowed down a lot more," Alvarez said, when asked of his late-season success. "I'm just learning how to play this game at this next level."
Alvarez is just the second Pittsburgh player to earn Rookie of the Month honors since 2005. Last season, first baseman Garrett Jones took home the award in July.
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.