After Kepler came around to score on a Kennys Vargas single, Chattanooga was still down by a run. That's when Walker stepped to the plate and did what he does best.
He connected on a deep shot to left-center to make it 8-7 and the Lookouts held on for a memorable win. Walker finished 2-for-4 with three RBIs and has 82 RBIs on the year.
Kepler finished 1-for-4, while Cubs No. 5 prospect (No. 92 overall) Billy McKinney and No. 19 prospect Jacob Hannemann both collected two hits.
Alex M. Smith is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.