Republic of Ireland midfielder Josh Cullen believes that Ireland can take positives from their World Cup qualifying campaign defeat to Serbia and use the performance as a platform to build on. 

Ireland went down 3-2 to Serbia in Belgrade after taking the early lead through Alan Browne before Dusan Vlahovic levelled. 

Two second-half goals from substitute Aleksandar Mitrovic put Serbia in front before a late goal from James Collins gave Ireland hope that would eventually be extinguished.

Despite the nature of the defeat, Ireland manager Stephen Kenny will go into Saturday's game with Luxembourg full of expectation, especially given how well his injury-hit side adapted to a new 3-5-2 formation. 

Cullen impressed in a makeshift midfield alongside Jayson Molumby and Browne and afterwards insisted that this Irish performance can be a foundation for long-term success. 

"It has to be," he told RTÉ Sport. 

"There’s positives to take from the performance and things that we know we need to work on areas to analyse and we’ll get better at. 

"It’s a starting point for us and now we just have to look to keep improving and use that as a base to build on for the rest of the campaign.

"Obviously we’re disappointed. We had every intention of wanting to win the game so, yeah, we’re disappointed with that but we just have to take the positives forward to Saturday."

From an individual point of view, Cullen can be happy with how he preformed against Serbia on what was his first competitive start for Ireland.

The Anderlecht player linked up well with Browne and Molumby and he's hoping to get another change to impress against Luxembourg in Dublin. 

"I was happy to play tonight and enjoyed the game but obviously would have enjoyed it a little more if we could have got a positive result. 

"It was an encouraging performance at times. Don’t get me wrong there’s still things to work on and we know that and things to improve on as a team – in possession and out of possession – I'm sure that will come in time. 

"So yeah, there’s positives to take but at the same time a lot to work on and we’ll be working hard to do that. 

"The bare minimum is to work hard and give as much energy as we can to the team. Every time you get the honour and the privilege to play for your country the bare minimum is to work hard and give all the energy you have."