The Northern Ireland wide man's name was erroneously omitted from manager Tony Mowbray's list of substitutes for the visit of the Rugby Park side.

However, while Lee Naylor - who was named on the bench instead of McGinn - sat watching the game from the players' lounge, the former Derry City man replaced fellow Irishman Paddy McCourt in the 66th minute with the home side cruising through goals by Aiden McGeady and Georgios Samaras.

And with his parents sitting in the stand having travelled over from Donaghmore, Country Tyrone, to see him in the hoops for the first time since he signed in January, the 22-year-old took an Andreas Hinkel pass and confidently drove past Rugby Park stand-in keeper Cameron Bell to seal the win.

McGinn was unaware of the team sheet confusion but admitted his goal made for a perfect day.

"My mum, Miriam, and dad, Paul, and agent Gerry Carlile, are over for the weekend to see me," he told Press Association Sport.

"It was the first time my parents have been over to see me play for Celtic.

"They missed my debut against Dundee United in September because they were on holiday so it was great to score for them and they were delighted.

"The team sheets must have been a mistake of sorts, I was always in the squad and it was great to get on.

"I have been thinking about my first goal since I joined the club in January and I'm just glad that it was in front of the Celtic fans as well as my parents.

"A year ago or so when I was playing for Derry City I could never have dreamed that I would one day be scoring for Celtic.

"It was a great ball through from Andreas Hinkel and I caught it on the half volley and it was such a special feeling when it hit the net.

"I didn't have any pre-planned celebration - I just ran to the fans.

"But although it was great to get the goal, it was so much more important that we got the win, we need to get the points to go with our performances."

McGinn and Celtic will face a stiffer challenge when they take on Hamburg in their Europa League clash in Germany on Thursday night.

With just one point from three Group C games, McGinn admits victory is essential if they are to have realistic hopes of qualifying through their section.

"It is a must-win game for us but it will be hard," McGinn said.

"Hamburg are a good side so it is going to be difficult but we will go over there with confidence after the result and performance against Kilmarnock.

"Hopefully we can get the early goal and then try to see the game out."

Celtic are three points clear of Hibernian at the top of the SPL table and four clear of third-place Rangers whose game against Dundee United at Tannadice today was abandoned at the break due to a waterlogged pitch with the visitors leading through a Steven Davis goal.

However, Mowbray will again make changes to his starting line-up for the European game.

"Hamburg is a different game," he said.

"We are away in Europe to one of the top teams in the Bundesliga.

"It is a big ask for us to go there and get a positive result so we will be set up differently.

"But we will go there with the confidence, knowing from the game against them at home where we lost 1-0, that they won't outclass us.

"There is a belief that we can make and score chances.

"If we can frustrate them and stay in the game and get opportunities, then hopefully they will go in."

One positive Kilmarnock manager Jim Jefferies took from the defeat was the performance of third-choice keeper Cameron Bell who was only playing because Alan Combe is out injured and Mark Brown, on-loan from Celtic, was not allowed to play against his employers.

"I had confidence in Cammy, he's a good goalkeeper with a good temperament and I thought he showed that," Jefferies said.

"He was excellent and if it wasn't for him, Celtic could have had a few more."