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The Scottish Premiership side lost 2-1 in the away leg of their tie, but won 4-2 on aggregate to secure a playoff clash against Club Brugge for a spot in the league phase of the Champions League.

Martin was pleased to see his team reach the next round of the competition, but insisted they have much to improve upon.

"We have to be really relentless," Martin said.

"So I am disappointed with the performance, I am disappointed with the result but there's lots to build on and we just need to be cleaner with the ball.

“There were some really good moments of football, we saw the game out really well in the last seven minutes, but there were way too many moments for them which were self-inflicted as well.

“I am disappointed we lost, we had some really good moments but I am disappointed how many shots we gave them, how many chances we gave them and also I’m disappointed with how many times we got in and around their box with an overload, big numbers and then don't execute the final pass.

"Jack Butland has been amazing, last week he had very little to do in this game and tonight way too much. We need to sort that out, but even with his decision-making with the ball at his feet he is selected really well so I have been really pleased with Jack."

Rangers already played out a 2-2 draw with Club Brugge in pre-season, coming back from two goals down to secure the draw in the friendly.

Martin believes his side cannot have a repeat of its second-leg performance against Plzen in the next round.

“We had an interesting game against them in pre-season, so we know a bit about each other and we have to be better than we were tonight for sure," Martin said.

“We had some really good moments like we did in the first leg tonight and didn't make enough of them.”