Daryl Murphy insists Celtic's 3-2 friendly defeat to Arsenal on Sunday has given everyone a boost ahead of their return leg against Braga.
The Bhoys have it all to do on Wednesday after slipping to a disappointing 3-0 first-leg defeat to the Portuguese side in their UEFA Champions League qualifier.
Former Sunderland striker Murphy, who scored at Emirates Stadium against the Gunners, retains the belief that Neil Lennon's troops can overturn their heavy first-leg defeat.
"It's encouraging to know we can score against a quality side like Arsenal, but there's no point if we keep conceding at the other end," he told the club's official website.
"We now have to tighten up for Wednesday because there is no room for error against Braga. We've given ourselves a mountain to climb after the result in Portugal.
"But with the fans behind us we'll create chances but we have to keep them out at the back. A clean sheet is imperative."
Murphy is pleased with his current level of fitness and insists he is raring to go should Lennon call upon his services against Braga.
"I feel I'm ready to start on Wednesday," he continued. "I have to be. It's up to the manager who starts against Braga but I'm ready for it.
"I've settled in well, the lads have been brilliant with me and made me feel at home straight away. I knew a few of them anyway and it's been easy to adapt.
"It's helped me getting a goal against Lincoln and then another against Arsenal. I showed that when I'm up front I'll get chances and I can take them."