With a pitching staff which has been decimated by injury in recent weeks and a struggling offense, Gateway (46-39) was coming off a 1-5 road trip and had lost nine of its last 12 games entering Friday.
For Grizzlies manager Phil Warren the scene on Friday was one he has seen a lot recently, as Gateway showed little signs of life after finding itself with an early deficit.
"We're playing terrible baseball. That's the bottom line. We're flat out getting what we deserve,'' Warren said. "We're playing terrible defense, we can't make a pitch when we need it, we can't get anybody in offensively.
"Winning is a habit and so is losing. Right now we're defining the word losing.''
Windy City (42-43) scored three times in both the second and third innings then got a two-run home run from Chad Cregar in the fifth and a three-run home run from Andrew Brauer in the sixth inning, as it took an 11-0 lead.
The Grizzlies finally got on the scoreboard against Windy City starter Daniel Cropper (7-4) in the sixth inning on a double by Michael Wing, a single by Chris McClendon and a run-scoring fielder's choice by Jet Butler.
Windy City answered with a pair of runs in the seventh inning on Cregar's third RBI of the night and a run-scoring single from Ryan Soares.
The Grizzlies scored twice in the bottom of the seventh as Jonathan Johnson had a RBI double and Wing added a sacrifice fly.
Baker (1-4) breezed through the first inning before an error by shortstop Michael Wing paved the way for three Thunderbolts runs in the second inning.
The lead grew to 6-0 in the third inning on RBIs from Jace Ray, Chase Tucker and Evan Button.