DONNCHA O'Callaghan admits his Warriors side must improve ahead of next Saturday's Aviva Premiership opener against Saracens at Twickenham.

The British and Irish Lion played in Cork against Munster on Friday night for the first time since leaving his hometown club last summer but it was the Irish side that ran out 52-21 winners on the evening.

And the experienced lock knows Warriors need to learn quickly before next weekend's Aviva Premiership curtain-raiser.

He said: "We need to step up as we have a massive challenge.

"Phil Dowson spoke brilliantly after the match and it's about character now in the squad.

"We need to find something deep inside from a players' point of view because in pre-season we haven't been able to reflect the work the coaches have put in."

With the new campaign just around the corner, O'Callaghan insists Warriors will be looking to progress this season and build on last year's 10th-placed finish.

He continued: "We want to drive forward and show we're getting better in the league.

"Last year there were an awful lot of games we were close in but if we're in the same position as last year we'll be disappointed as we want to improve on that.

"We need to kick on. We have a really good structure and really good coaching but in recent weeks we haven't been able to reflect it on the pitch."

O'Callaghan spent 17 years with Munster before joining Warriors last summer and spent time thanking fans after Friday night's pre-season game.

He added: "I'm unbelievably grateful to everyone. It's so nice for people to come out and I'm humbled. I don't have the words to say apart from thanks very much.

"It's not supporters because I knew them all. It's neighbours, family and friends, which is what all this represents."