The Lord's dream is over for Gloucestershire for another year, but captain Alex Gidman could wake up with a clear conscience this morning.

Perhaps wrong to insert hosts Sussex after winning the toss, Gidman hit 116 off 117 balls – a career best in one-day cricket – to set up a semi-final sizzler.

Half-centurion Hamish Marshall also excelled, yet neither was able to outshine a near-perfect innings by Ed Joyce.

The Irishman clattered 146 from 139 balls, aided by a run-a-ball 60 from Murray Goodwin, to put the Sharks in clear waters at Hove.

Gidman's decision to bowl first beneath the baking sun quickly looked dubious, as Joyce and Chris Nash raced to a half-century opening partnership inside nine overs.

They had reached 62 when Nash was cleaned up by a rapid delivery by Steve Kirby, after which the brutality of Luke Wright's hitting meant momentum remained squarely with the hosts.

Gidman attempted to rein them in with spin at both ends, and he at least saw the back of Wright when the England Twenty20 man holed out to James Franklin off Richard Dawson.

Vikram Banerjee was less fortunate, shipping plenty before being involved in the game's most controversial moment in the 33rd over.

Joyce smacked Chris Taylor to long leg, where Banerjee claimed the catch. Even the batsman thought he had come a cropper, but he was able to retrace his steps and add six to his score when TV replays showed Banerjee's foot had touched the rope.

Cue plenty of vitriol towards the young spinner from the home faithful, but jeers were replaced with rapturous applause when Joyce reached his ton in the next over.

It was a stupendous knock, matched in the entertainment stakes by Goodwin as the pair cashed in on virtually every loose delivery.

Goodwin was annoyed to get cleaned up by Jon Lewis attempting a cheeky paddle, and he was quickly followed by Dwayne Smith when Hamish Marshall clutched a steepling catch off Dawson.

Run-outs accounted for Rory Hamilton-Brown and finally Joyce in the 48th over, shortly after he had been dropped in the deep by the luckless Banerjee.

Kadeer Ali fell in only the second over in reply, trapped leg before by James Kirtley, but Gidman and Marshall were unruffled in matching the required rate. The Gloucestershire CCC skipper was happy to dominate the strike, belying his recent patchy form, and his more powerful strokes were the perfect complement to Marshall's guile.

Both men cruised past 50, but sharp fielding from Joyce saw Marshall caught short of his ground and the 155-run stand broken.

It felt like a crucial blow, even more so when Craig Spearman was adjudged leg before to Hamilton-Brown in the next over.

An eventful 35th over saw Gidman reach three figures and lose his partner to the very next ball – Yasir Arafat sounding the death rattle by dismissing Chris Taylor.

The visitors needed 78 off the last 10 overs, but lost Gidman with 9.3 still to go when he was given out caught behind attempting to leave Michael Yardy. A sharp stumping off Nash by Sharks keeper Andrew Hodd accounted for his opposite number Steve Adshead, and the game was up when Franklin fell to the same man.