Celtic manager Brendan Rodgers is sure his side can improve in the Champions League – if they strengthen the squad.

The Scottish champions closed their campaign with a 2-1 win over Feyenoord on Wednesday to finish on four points, having already been consigned to bottom spot in Group E.

A first victory in 16 Champions League games will allow Celtic the opportunity to go into next season’s tournament, if they qualify, with a fresh start but Rodgers stressed they need to add players over the next two transfer windows.

Only one of the club’s eight summer signings, Luis Palma, started the game against the Dutch champions.

Rodgers said: “I think over the course of the competition we have shown lots of moments of potential, especially at home. We could have been sitting with nine points just from the home games.

“It has been a challenge with key players being out, but over the course of the six games I have seen enough in how we have played and how we fought that if we can strengthen this squad and add quality in key areas we can take the confidence from this victory and look to qualify again next year and see if we can push on, if we arrive in this competition again.

“But you have to have certain qualities to perform at this level.

“There’s a number of things we have to do to bridge the gap. We have to play in a way that makes it really difficult for teams, surprise teams with the quality of our football.

“But there’s no doubt, you can’t get away from it, we have got to have a deeper squad of players to compete at this level.

“I said to the players before the game, this is a competition and a level which can dent your confidence, but when you finish it, you will be better players for it and will have gained valuable experience, and you are still very good players that are in a process and, with some help, you will improve.”

Liam Scales is the best example of a player who has grown through the tournament. The Irish defender was on loan at Aberdeen last season but has been an ever-present in the Champions League and won the man of the match award against Feyenoord.

“I thought he was excellent,” Rodgers said. “Scalesy has come in and shown, from pre-season, a player who was maybe unsure about his future, can come in and consistently play and in the Champions League in the main has played very well.”

Scales feels he has grown throughout the tournament.

The 25-year-old said: “Over the six games we gave had tough stages, we have played with nine men, played with 10 men, and I have had to dig in and learn how to cope at this level.

“I feel like Wednesday was the peak of it for me. I am just glad I could help the team to get the win and it’s a nice personal achievement as well.

“I think we deserved it. We were really good in the first half, we took the game to them, and when we had to defend in the second half, we did. To concede a late goal and then come back and score was brilliant, we showed great character.

“We are all delighted. On paper it didn’t mean much but to us it meant a lot. We were all desperate to get a win in this campaign.

“I feel like our home performances were all quite good. Just away let us down. We need to learn from that and I’m sure we will.”