Disappointed Joe Aribo admits Rangers "lost their focus" in Saturday's 3-3 draw with Ross County.
And he's challenged his teammates to up their game ahead of Wednesday's date with destiny against Celtic.
Rangers battled from 2-1 down to lead in Dingwall with Connor Goldson's header sparking bedlam in the away end.
But a second error from Allan McGregor allowed County youngster Matthew Wright to slam home a 96th-minute equaliser that saw Rangers drop points for a second straight away game.
The Premiership leaders had only conceded one league goal under Gio van Bronckhorst heading in but they shipped three to County. And Aribo, back in the side after returning from AFCON, couldn't hide his deflation.
He told Rangers TV: "We're very disappointed. We lost focus a few times and gifted them three goals - you can't do that away from home.
"It's very disappointing because we gave it our all.
"We were 2-1 down at half-time and knew we had to give ourselves a reaction and we did that, going 3-2 up.
"So to concede so late on and it being another mistake was bitterly disappointing."
However he warned his teammates there is no time to feel sorry for themselves with Celtic gunning for them on Wednesday night.
"You can never dwell on performances, good or bad," he said. "We have to dust ourselves down and get ready to put in a good performance on Wednesday."
On a more positive note, Aribo had plenty of praise for new signing Amad Diallo who scored the opening goal and had a big hand in the second.
He went off injured in the second half and it remains to be seen how serious that problem is.
But Aribo was delighted with what he saw before he went off as he said: "You could see that he was a constant threat every single time he got on the ball, and he got on the scoresheet.
"He's getting his numbers in already and that's very good to see."
