But the goalkeeper gave his former team a gift on Friday, and they gratefully took advantage.
The Fire hosted Vancouver Whitecaps FC at SeakGeek Stadium on MLS Friday Night on TSN, and with the game scoreless early in the second half, Ousted ventured too far out on Jon Erice's floating cross, then tried to prevent handling the ball outside of the 18-yard box. As he pushed the ball away, it went straight into the path of Yordy Reyna, who pounced and scored in the empty net.
GOAL: Yordy Reyna takes advantage of a David Ousted mistake
Ousted, who played for the Whitecaps from 2013-17, inadvertently offered a break to a player and team that haven't seen many so far this season.
The Whitecaps entered Friday's match winless in 2019, with just one point earned through five games. While they didn't end up winning, as the game ended in a 1-1 draw, it did lead to another result for a team desperately working for points at this point.
And Reyna, who is coming off his best season in MLS, when he scored six goals and 11 assists, hasn't been able to get on track yet, so the goal in Chicago could kickstart his season.
Reyna's head coach, Marc Dos Santos, admitted at training this week he's still trying to get a beat on the Peruvian's abilities.
"Yordy has been unstable," Dos Santos said to reporters. "I believe in the tools that he has. I think he is a 1-v-1 player that can create things, that can be a player that at any given moment can make a difference. What I'm still learning about Yordy is it kind of drifts. There's high moments and then there's very low moments."
Dos Santos seemed to evoke FIFA ratings in trying to find consistency in Reyna's output moving forward.
"I have to find a way as a coach to try to find, Ok, instead of being 80 and then 15, and 75 and 20, can he be a 70 guy all the way? That's where I want to find to help him."
For his part, Ousted owned up to the gaffe after the game as he faced reporters.
"I made a mistake, simple as that. I told the guys when I got in the locker room that, I apologized for putting us in that hole and it was a mistake from my side. It hurts, especially in a game like this where we needed three points, and I think we had the majority of chances, but that's the nature of the position," he said.