The right-handed reliever began the day looking for work, and by the end of it, he was halfway across the continent pitching for the Texas Rangers in their game against the Blue Jays at Rogers Centre.
And if that wasn't crazy enough, O'Day entered the game wearing another player's jersey.
So, Darren, how was your day?
"It was interesting to say the least," O'Day responded with a slight smile, just minutes after he surrendered the game-winning hit in Toronto's 8-7 win over Texas in 11 innings.
The strangeness of the day began at 12:45 p.m. ET, when O'Day was at home in Panama City Beach, Fla., and got a call from his agent, who said the Rangers had claimed him on waivers and were calling him up to the big league roster. O'Day had just been designated for assignment by the Mets this week.
Rushing to the nearest airport, O'Day boarded a flight to Memphis and then transferred to a flight heading to Toronto, to join the Rangers.
O'Day got off the plane in Toronto at about the same time the Rangers' game was in the eighth inning -- 9:45 p.m.
"The travel secretary was texting me back and forth," said O'Day. "The original plan was to go to the hotel, but he said, 'Go to the field, we might need you.'"
Sure enough, as the Rangers' bullpen was running out of arms in the extra-inning affair, O'Day's services were needed. The right-handed reliever arrived at the ballpark during the 10th inning of the contest, when he found out the team did not have a jersey made for him.
While on the road, the club's equipment manager usually carries around the jerseys of several players who could possibly get called up, and of course, O'Day was not one of those players. So O'Day was forced to don the jersey of Kason Gabbard -- who is currently with Triple-A Oklahoma City.
"Yeah, that's a first," O'Day said. "I figured I'd be throwing in the mid-90's -- doesn't [Gabbard] throw pretty hard?"
O'Day was brought into the game with two runners on base in the 11th inning, and had his first encounter with his manager, Ron Washington, on the Rogers Centre mound.
"He was excited, and the first thing that he said was, 'Let's rumble,'" Washington said.
O'Day was to face Jays first baseman Kevin Millar, who was obviously confused at the name on the jersey.
"Gabbard?" Millar said with a laugh. "I thought that was a left-handed pitcher. [O'Day] came in throwing a sinker ball, side-armed, right-handed. I was a little confused at first."
Millar's confusion didn't last long though, as he drove a pitch from O'Day into the left-center-field gap, giving the Jays a walk-off victory and bringing an end to the pitcher's turbulent day.
"I'll remember the day, not the outing," O'Day said.
David Singh is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.