After singling in the top of the second, Spencer popped out twice before giving the Smokies an 8-2 lead in the seventh inning with his grand slam. In his next at-bat, Spencer cracked his 14th homer of the year.
His big night gave Spencer four homers and 11 RBIs over his last six games. In 82 games at Double-A Tennessee this season, Spencer is batting .281 with 26 extra-base hits and 49 runs driven in.
Originally drafted by Philadelphia in 2007 out of Arizona State, Spencer was sent to the Oakland A's organization in 2008 in the deal that sent pitcher Joe Blanton to the Phillies. He was later traded to the Cubs in a trade that sent Jake Fox, Aaron Miles and cash to Oakland.
Also for the Smokies (66-43), Tony Campana tripled, doubled twice and singled while Chris Archer improved to 6-1 by allowing two runs on five hits while striking out five over six frames.