John Collins believes Celtic's 2-2 draw against Ajax in Amsterdam on Thursday night has done "wonders" for the players' confidence.
The Hoops went into their Europa League Group A opener against the Dutch side looking fragile after losing their lead at the top of the Scottish Premiership to Aberdeen and under some pressure having dropped out of the Champions League at the play-off stage against Malmo.
However, Ronny Deila's men put in an assured display in the Amsterdam ArenA, leading 2-1 with goals from midfielder Nir Bitton and right-back Mikael Lustig before Emilio Izaguirre was sent off for picking up the second of two yellow cards and Ajax substitute Lasse Schone equalised.
Ahead of the home league game against Dundee tomorrow (3pm) assistant manager Collins expressed his delight at getting back on track.
The former Celtic midfielder said: "I was very happy. I thought we bounced back well.
"It does wonders, a good performance and good result.
"That's what brings back the confidence.
"I think maybe a little bit of confidence had dropped a little bit.
"But as the game went on I think you could see the confidence coming back into the players and there were a lot of very good performances against a very good team.
"We got the balance right defensively and as the game went on I thought we grew into it, our passing got better and we created chances away from home.
"Overall, very pleased, but I don't think we were in that big of a slump. Okay we lost the game last week but a few weeks ago we were playing terrific (football).
"We had a little dip and we want to follow last night's performance up with another good performance on Sunday."
Collins was further encouraged by the performance of Kris Commons.
The midfielder celebrated his first start in Europe this season by setting up Bitton for his eighth minute goal before crossing for Lustig to head the visitors back in front, after Viktor Fischer had levelled.
The former Hibs boss said: "Kris came into the team and was terrific. He did his defensive duties very well and again had the magic in and around the opponents' box.
"He came up with the goods, an excellent pass for the first goal and deliveries at set-pieces was 10 out of 10.
"He was a big performer for us."