Stewart went 2-for-4 with a walk, a home run, two runs scored and two RBI in Friday's 10-8 win over the Cubs.
The 22-year-old slugger took David Peterson deep in the fifth inning as the Reds put together a comeback from an early 3-0 deficit. The long ball was Stewart's 29th of the season, and his 102 RBI lead the majors -- putting him on pace to become the third rookie in history to lead the league in that category after a pair of Red Sox, Walt Dropo in 1950 and the legendary Ted Williams in 1939.