CLONTARF produced one of their greatest Castle Avenue performances to send champions and league leaders Shannon to their first AIL defeat since December 2004 and boost their chances of a top four spot.

Coach Phil Werahiko's men ran in five tries . . . four of them coming in a blistering first half performance . . . to jump from fifth to third in the table and achieve a feat last attained by Belfast Harlequins in December 2004.

Shannon were not at their best by any means but they were never allowed to play by a majestic Clontarf outfit who took the game to the visitors and scored a series of brilliant tries that will surely boost their confidence ahead of their visit to Garryowen next weekend.

"I am just so overwhelmed with the match, " said Kiwi Werahiko. "Our lads really did play some amazing rugby out there. You always feel that even when we were scoring tries that Shannon were going to come back. That's the kind of club they are. It's the nature of the club they are and I was always delighted to get the result. The key was to go and try to play rugby with Shannon. If you try and take the play to Shannon, nine times out of ten you won't come away with a result.

"So we just tried to change things up a little bit and when we had the ball we tried to ask questions of Shannon and I guess we found spaces where probably very few have.

"You'd be delighted to win by a point or two points. But to get a result where there are a number of points being scored against a club like Shannon is unbelievable. It's a great day for Clontarf."

The Dubline side got off to a brilliant start when second row Ben Gissing touched down after just five minutes.

Darragh O'Shea failed with the conversion attempt and while Dave Delaney landed a long-range penalty to reduce the arrears just two minutes later, it wasn't long before Clontarf were celebrating another superb try.

After 10 minutes, scrum half Fiach O'Loughlin broke out of defence and with the support of his pack, the ball was quickly spread wide to centre Marc Hewitt who combined with winger Derek Keane to send outhalf Peter O'Brien on a 50-metre sprint to the line.

O'Shea again failed with the conversion and while Delaney replied with a 15th minute penalty to make it 106, Shannon struggled to cause Clontarf any major problems until flanker John O'Connor intercepted Niall O'Brien's pass in his own 22.

The Shannon man sprinted the length of the pitch and looked certain to score before he was tackled into touch near the corner flag.

That proved to be a major turning point in the game and O'Brien made up for his earlier mistake by taking a reverse pass from O'Shea on halfway to scorch up the touchline and score Clontarf 's third try under the posts on 32 minutes.

O'Shea's conversion made it 17-6 and the gap was soon five points wider when a brilliant back-line move sent the fullback in for Clontarf 's fourth try and a bonus point just a minute before the break.

It was too much to expect Clontarf to surrender a 22-6 half-time lead and they increased their advantage on 49 minutes with a Breiffne O'Donnel try, converted by O'Shea to move 23 points clear. Shannon grabbed consolation tries through substitute prop Tony Buckley on 57 minutes and winger Fionn McLoughlin in injury time with Clontarf outhalf O'Brien kicking a cheeky long-range drop goal in between.

"Next week against Garryowen is going to be the same as well, " added Werahiko.

"Let's see if we can live up to today's performance. We can't say that Shannon were at their best and we also know that there are a number of players that are unavailable to them yet.

"But come the top four they will all be back. After a defeat like this I'd hate to be the side that has to play Shannon next."

That privilege will fall to Blackrock College.

CLONTARF D O'Shea; N O'Brien, M Hewitt, B O'Donnell, D Keane; P O'Brien, F O'Loughlin; K Dorrian, N Carson, R Sweeney; A Trenier, B Gissing; M Coetzer, J Ellison, P Purdue. Subs A Wood for Gissing, 46 mins; D Lambert for Ellison, 69 mins; D Geraghty for Purdue, 78 mins; M Rantz-McDonald for N O'Brien, 80 mins

SHANNON D O'Donovan; P O'Connor, B Tuohy, E Cahill, F McLoughlin; D Delaney, F McNamara; L Hogan, S Cronin, F Roche; T Hogan, P O'Brien; D Ryan, J O'Connor, E Halvey. Subs C McMahon for P O'Brien 49 mins; T Buckley for Roche, 49 mins; C O'Loughlin for F McNamara, 65 mins; A Meany for J O'Connor and TJ Hickey for Cronin, 76 mins Referee C Stanley (URS)