Sussex Sharks admit it will be win or bust when they pack another big Twenty20 Cup crowd into the County Ground tomorrow night.

Chris Adams' men went down by five wickets off the last scheduled delivery of a rain-curtailed thriller with Surrey Lions last night.

They set Surrey a revised 114 in 13 overs after an hour-long stoppage for rain and the visitors got there when Azhar Mahmood fired a six and two fours off the last three balls.

Sussex, who host Hampshire tomorrow, now face a major battle to reach the knockout stages.

Skipper Adams said: "To reach the quarter-finals I said you would have to win five games.

"We've won one and we've got four to go so the maths is easy.

"We were three balls away from winning a great game.

"We had high hopes. We knew we had to be at our best to beat Surrey and we were very close."

The skipper defended his decision to entrust the last over to the left-arm spin of Mike Yardy rather than the pace of renowned last-over bowler James Kirtley.

He said: "It was a big call but he had bowled so well to get us back in the game."

A crowd of 5,500 saw the contest and tomorrow's game with Hampshire (6.30pm) looks set to sell out.