Crow issued consecutive bases-loaded walks during Toronto's three-run eighth inning, sending the Royals to a 4-2 loss to the Blue Jays on Saturday.
"Throwing eight straight balls, it's a terrible way to lose a game," Crow said.
The Royals, who trailed Tampa Bay by 6 games for the second AL wild-card slot at the beginning of the day, lost their second straight following a five-game winning streak.
Kansas City failed to capitalize on a strong start by right-hander Jeremy Guthrie, who allowed one run and eight hits in seven innings.
"Tremendous game from him," Royals manager Ned Yost said. "He was still strong going into the eighth inning."
Rather than stick with Guthrie, who was at 92 pitches, Yost turned it over to his relief corps, who came in with an AL-best 2.56 ERA and had allowed just one run in their past 14 2/3 innings.
"My mindset is, `OK, we've got a one-run lead, we've got the best bullpen in the American League, let's get three outs and get to [closer Greg Holland],'" Yost said. "It just didn't work out, we couldn't get it done."
Instead, the Blue Jays batted around while scoring three unearned runs against four relievers. Kansas City shortstop Alcides Escobar helped the Blue Jays with a key error.
Pinch hitter Munenori Kawasaki led off with a single against Kelvin Herrera (5-7), and went to second on a bloop hit by Jose Reyes. Will Smith came on to face Ryan Goins, who hit a potential double-play grounder that Escobar couldn't handle, allowing Kawasaki to score from second.
Escobar said his line of sight was blocked by Kawasaki on the crucial play.
"I make that play all the time," Escobar said. "I didn't see the ball, that's why I missed that. The guy blocked me."
Edwin Encarnacion walked to load the bases and Crow came on to face pinch hitter Mark DeRosa, who struck out on three pitches. Brett Lawrie and Rajai Davis each followed with four-pitch walks, giving the Blue Jays a 4-2 lead.
"We can't be coming in and doing that at this time of year," Yost said. "We've got to command the ball a little better in these crucial situations. Aaron does, anyway."
Upset at the ball four call to Davis, Yost was ejected for arguing with plate umpire Will Little when he came out to replace Crow with Tim Collins, who retired pinch hitter J.P. Arencibia to end the inning.
"I'd just seen enough," Yost said. "You don't miss a pitch in a crucial situation like that. If he throws a ball, OK. But I think the replay will show it was definitely a strike."
Yost, who was ejected for the first time this season, also argued with Little over a call at first base in Friday's 3-2 loss.
The late rally made a winner of knuckleballer R.A. Dickey (11-12), who allowed two runs and seven hits in eight innings.
"I changed speeds quite a bit today," Dickey said. "I was able to keep the slower knuckleball down and get some outs with it. Anytime you can add and subtract speed in the strike zone, you're going to have a better chance of your opponent mis-hitting balls."
Royals outfielder Alex Gordon had two assists, throwing out Goins at third in the first and getting Josh Thole at second in the seventh. Gordon boosted his major league-leading total to 14. It's the fifth time he's had two assists in a game.
Kansas City opened the scoring in the second. Salvador Perez drew a one-out walk, moved up on Jarrod Dyson's single and scored on a base hit by Escobar.
The Royals made it 2-0 in the third when former Blue Jays infielder Emilio Bonifacio led off with a triple and scored on Hosmer's single through the left side.
The Blue Jays ran into another out on the bases in the third when Reyes was thrown by right fielder David Lough as he tried to stretch a single into a double. Escobar made a diving tag to retire Reyes for the second out.
Toronto broke through against Guthrie in the seventh when Rajai Davis hit a two-out double and scored on Josh Thole's single. The inning ended when Gordon threw out Thole trying to stretch his hit into a double.
"We're lucky that didn't come back to bite us," Blue Jays manager John Gibbons said.
The Blue Jays will activate RHP Steve Delabar (shoulder) and RHP Dustin McGowan (shoulder) off the disabled list Sunday. ... Goins' first-inning single gave him an eight-game hit streak to start his career, matching Jesse Barfield's 1981 Blue Jays record. ... Encarnacion's fourth-inning single was the 1,000th hit of his career.