Adam Olbrychowski made his Senators debut and went the first 4.2 innings and allowed three runs and pitched effectively but took the loss. Paul Demny and Pat McCoy also pitched in the game.
Bowie scored two in the seventh and single runs in the eighth and ninth innings to break open the game.
The Senators offense managed just a pair of two-out singles in the first and in the second until the back-to-back home runs in the ninth. Rendon and Seth Bynum had the two singles.
Harrisburg finishes their season 64-78 and misses the playoffs for the first time in three seasons. Bowie previously clinched a playoff spot and opens their Western Division Championship Series on Wednesday at home against Akron.
The Senators next home game is the 2013 season opener against Bowie on Thursday, April 4, 2013 at 7:00 p.m.