When all was said and done, San Diego outlasted the Cubs 5-4 in 11 innings on Khahil Green's two-out RBI single off Ryan Dempster on an 0-2 pitch, paring their wild-card lead to one game.
"I missed the play," he said. "That's all I can tell you."
The Padres trailed 2-0 in the sixth and had a man on first with no outs when Rich Aurilia drove a pitch from reliever Jon Leicester up the middle. Mark Grudzielanek corralled the ball while sitting down and made a short flip to Nomar Garciaparra at second for an apparent force.
Garciaparra caught the flip while gliding across the bag, touching it with his right foot before making a wild throw to first base that bounced over the dugout and into the stands.
But Froemming ruled Garciaparra was off the bag when he caught the ball. Terrence Long was sent home and Aurilia was awarded second on Garciaparra's throwing error.
"I thought I caught it on the bag, and that was the argument to the umpire," Garciaparra said. "The ump thought I was on the other side. I don't know what the actual thing was."
Baker was livid over the call, which came two games after another disputed Froemming call led to Mark Prior's unraveling in Tuesday's loss.
"The replays clearly showed [Garciaparra] touched the bag," Baker said. "And then the base-runner (Long) had to avoid Bruce to get in there in the first place, and he slid way out and did a tumbling slide [into Garciaparra] that's supposed to be illegal. There were a lot of bad things that went wrong on that play.
"It was a tough one to lose."
Froemming later watched replays and saw he was wrong.
"You don't like it to happen," Froemming said. "On the field I had [Garciaparra] coming across the bag. I came in here and looked at the replay. I wanted to know if I had it right. I don't know what it was. He absolutely got me."
One batter later, Jay Payton appeared to strike out while trying to check his swing, but first base umpire Kevin Kelley ruled he didn't go around. Plate umpire Tim Timmons then ejected Cubs pitching coach Larry Rothschild for arguing the call.
After Leicester walked pinch-hitter Dave Hansen with two outs, Green doubled off the vines in left-center, tying the score and denying starter Matt Clement a chance at the win. Following the second rain delay, the Padres took a 3-2 lead in the seventh on Long's RBI triple off Kent Mercker.
But Garciaparra's two-run, seventh-inning homer into the basket in the no-beer section in left field put the Cubs ahead and turned Wrigley upside-down for one short-lived moment.
After Kyle Farnsworth gave up two singles in the eighth, Brian Giles tied it again with an RBI single off Mike Remlinger, also on an 0-2 pitch.
The Cubs put men on base in the eighth, ninth and 10th innings, but were hitless in six at-bats trying to get the runners home. The Padres stranded 18 runners on the afternoon, but the Cubs went 2-for-13 with runners in scoring position to even things out.
Sosa was 0-for-5 with four strikeouts and was booed heavily by the crowd of 39,054. He's hitting .114 in his last nine games (4-for-35) and trying to deal with what has become an increasingly impatient fan base.
Asked if he'd seen Sosa struggle like this before, Baker said: "Not since I've been here. It looked like he was coming out of it [Wednesday], but it's a hot-and-cold situation."