Why it matters: Stewart's challenge lead adds another distinction to his rookie season after he entered September with 31 homers and 105 RBIs, drawing an NL Rookie of the Year endorsement.
By the numbers: Stewart won 26 of 46 challenges, a 56.5% success rate, in [ESPN's September 7 tracker](https://insider.espn.com/mlb/story/_/id/48305211/crossDomain).
What to watch: The remaining September games will determine whether Stewart finishes the season atop the hitter challenge rankings.