Rangers forward Steven Naismith feels the team put in their worst display of the season in defeat to Valencia.
The Scottish side went down 3-0 to the Spaniards in the UEFA Champions League on Tuesday night, their first defeat of the season.
Naismith was at the centre of Rangers' limited threat, striking the post on two occasions with 74 lacklustre minutes in between.
"I think it's the worst we've played since the start of the campaign," Naismith told Sky Sports.
"We started off pretty well and I had a shot - when I looked up it was heading for what I thought was a goal, but it hit the post.
"But the biggest disappointment is we lost a goal from a set-play, throughout the campaign we've been good like that."
When asked if it was his most frustrating game of the season, Naismith replied: "Certainly in front of goal it was.
"We didn't defend great and we didn't take the chances when they came along, that's probably the summary of it."
Team-mate Madjid Bougherra added his input to the disappointment, as Rangers let go of their hold on second place in Group C with just two games left to play.
"We are really disappointed," added the Algeria international, who is still reeling from the sides' 1-1 draw at Ibrox two weeks ago.
"We still have many regrets from the first game at home. We needed to win it, but today we had the first good situation, hitting the post and, if he'd scored, the game changes.
"But we tried to keep together but Valencia looked good. They're very good, to be honest."