ALL it takes is one goal. That was the message from Partick Thistle striker Kris Doolan ahead of his side’s Scottish Cup fifth round trip to Parkhead today, where he hopes to encounter a Celtic side with one eye on the Europa League.

Brendan Rodgers’ team has dominated the domestic scene again this season and remain on course to defend their treble, but Kilmarnock’s 1-0 victory over the champions at Rugby Park last Sunday has given Doolan faith that Thistle can get a result if they keep things tight at the back.

And with a crucial European knock-out clash against Zenit looming on Thursday, the 31-year-old is hoping to catch the home side off guard and net his first Parkhead goal in the process.

“If we can pick any weakness in them then great,” he said.

“That’s what we have to do. We know they are streets ahead of everyone in the league. But Kilmarnock showed last weekend it only takes a goal.

“Kilmarnock also defended very well. If we can do that then there’s no reason why we can’t progress to the next round of the cup.

“I’m sure Brendan Rodgers and the Celtic players will have an eye on the European tie. I’ve no doubt they will have their focus on the cup game but I’m sure they will still be looking towards Zenit. European football is where Celtic are judged and hopefully we can catch them off guard.

“I would love to score at Celtic Park. I’ve scored at most of the other grounds but a goal at Celtic Park still eludes me. But there is no reason why I can’t change that on Saturday.

“I’ve had a couple of chances there in the past, a couple that I thought were heading into the net. But Craig Gordon is a bit big and he’s clawed a few out of the corner."

Victory for Celtic this afternoon would see them take another step towards successfully defending all three major domestic trophies, having already secured the Betfred Cup in November and built up an eight-point lead at the summit of the Premiership table.

However, Doolan warned the champions that their task will be harder this time around due to an increased challenge from their competition in Scotland.

“The fact they won the treble last season was incredible,” said the striker. “To do it back-to-back would be amazing. I would like to think it would be tougher this season.

“Teams might be a bit wiser and starting to take points off them in the league. But the gulf is still big. If they do it this season I think they will have to work harder because teams are pushing them harder.

“When we have been to Parkhead we have run them pretty close. We’ve not come away with the win, but we’ve drawn and been close to another draw (in January 2016) when Leigh Griffiths pops up in the last minute and they get the win. It’s about us getting over the line and getting that win we all want.”

A cup meeting between these two sides will forever have Jags fans reflecting on one of their greatest moments, the 1971 League Cup final.

Thistle routed their illustrious neighbours 4-1 at Hampden Park, despite having just achieved promotion that season and facing a Jock Stein side that had competed in the European Cup final the year before, and the significance of that day 47 years ago is not lost on Doolan.

“That’s the romance of the cup,” he said. “That’s why the Scottish Cup means so much to people in Scotland. It’s not lost any meaning for players or fans.

“You can have your name in lights and that’s the carrot everyone here is going for.”