THE world turned with seismic effect in yesterday's Bank of Ireland All Ireland semi final at Croke Park. It, wasn't so much the fact of Mayo's win that caused such surprise - although that did, cause enough - but the comprehensive manner.

So the logbook of manager John Maughan's achievement with this team that he took on in Division Three of the National League saw the completion of its latest remarkable entry.

Kerry, with a very poor display failed to do themselves justice and only Maurice Fitzgerald delivered on his reputation with a flawless display of dead ball kicking. In the last 30 years, most people have forgotten what an under achieving Kerry side looked like, so the sight of Connacht champions moving with greater purpose and efficiency than their Munster counterparts was unusual.

Even Mayo's couple of weaknesses ended up illustrating a strength. Having been unable - largely because of a freak goal let in by goalkeeper John Madden - to put more than two points between themselves and Kerry by the end of the hour, the winners showed great composure in remaining calm and outscoring Kerry in the last 10 minutes, 1-2 to 0-1.

The match started with Mayo having to bring in veteran corner back Dermot Flanagan to replace Anthony McGarry who took ill on Saturday night. Kerry switched their corner backs and avoided the jarring aesthetics of big Ray Dempsey being marked by not so big Charlie McCarthy.

The tone of the whole match was swiftly set. Maurice Sheridan kicked a free in the second minute after Mike Hassett fouled Mayo full forward John Casey. Casey scored the second, six minutes later. The difficulties Kerry suffered on the full back line defined the match.

There had been considerable debate about whether Hassett, a fine wing back, was going to cut it as a championship full back at the top level and also on the apparent anomaly of Hassett playing on the square while Sean Burke lined out at centre back.

Advocates of the switch were, however, a little undone by the fact that after the two players had exchanged places for the second half, Burke got a fairly identical roasting from the rampant Casey. Not alone did the Charlestown player kick four points but he was also fouled for another three converted frees.

It can be argued that had the move been made immediately, Casey mightn't have hit top gear so easily but you wouldn't want your house on the likelihood. Beside Casey, corner forward David Nestor was causing similar problems.

McCarthy was in difficulties on the turn and twice Nestor cut through for clear goal opportunities. One, in the 15th minute, set up Casey only for O'Keeffe to block the effort and the Kerry goalkeeper came to the rescue again 13 minutes later when putting Nestor's shot out for a 45.

Kerry's efforts at keeping in touch were also symptomatic of the afternoon. Maurice Fitzgerald kicked all their points in the first "half and all but two of their total for the match. His free taking was flawless and might have been more influential were it not for the very creditable competition from Mayo's Maurice Sheridan who equalled Fitzgerald's total of six.

All around the pitch, the Munster champions were in trouble. Their midfield hadn't been the most forceful during the championship to date but yesterday it struggled terribly. Dara O Se improved on his performance in the Cork match but he was assisted by Mayo's replacement midfielder Pat Fallon taking so long to get into the match.

Seamus Moynihan played on Liam McHale and was unable to prevent the big Mayoman from making a fine start and later in the match, he was tied up so much in his own defence that he wasn't in a position to make his customary excursions into opposition territory. McHale faded later on and there were fears that he might have suffered a recurrence of the hamstring injury that afflicted him earlier in the year.

The final piece in Kerry's jigsaw of woe was that the forwards were operating on short rations. Fitzgerald did what he could - eight points and no wides - and Genie Farrell drew fouls at a profitable rate - four, all of which yielded points - but the overall impact was muted compared to the Munster final.

Neither Billy O'Shea, expertly shadowed by Pat Holmes, nor Dara O Cinneide were in form and the attack looked blunt. Mayo's tactic of playing Colm McMenamon in behind the half backs worked a treat. McMenamon cleaned up a bundle of loose ball and helped congest the traffic when Kerry were trying to launch quick moves.

In general, Mayo's defence was outstanding. Kevin Cahill and Kenneth Mortimer gave little away on the full back line whereas the half backs were outstanding. Captain Noel Connelly and Holmes conceded nothing and centre back James Nallen coped tolerably well with Fitzgerald. His leadership and penetrative runs from the back were the most notable aspects of his contribution.

In the 31st minute he started a move on his own 40 and ran to the other end of the pitch to take a final pass from McHale and crash the ball to the net.

An incident straight from the Mayo, God help us handbook followed. From the kick out, Sean Burke took possession and launched a long kick from the middle of the pitch. The ball ran past Madden, who was out of his goal, and into the net.

The manner of Mayo's response was impressive. Nestor kicked a point in immediate reply and Mayo added two more before the interval.

Kerry's half time changes didn't make much material difference. Too often, the diminutive Farrell found himself under, high ball from his team mates and they still relied heavily on Fitzgerald's frees. Brian Clarke and Denis Dwyer came into the attack but afforded little enhanced penetration. At the back neither Burke nor substitute Johnny O'Driscoll (on for McCarthy) made much impact on Mayo's full forwards.

Still, there were only two points in it with 10 minutes to go. Five of those minutes failed to cut the deficit before Mayo stamped their authority on proceedings. Sheridan kicked his final free in the 66th minute and a minute later, James Horan cleverly lobbed O'Keeffe from out on the wing and the ball dropped into the net to give the winners a six point margin. It could have been 10.