ARUL Suppiah's career-best 131 and an exhilarating 54-ball century from Peter Trego led Somerset to an astonishing four-wicket LV County Championship victory over Yorkshire at Taunton.

Set a massive 476 to win in a minimum of 90 overs yesterday, the home side reached their target with 4.3 overs to spare. It was the second highest successful run chase in the Championship's 145-year history, the fourth highest in first-class cricket in England – and the eighth highest of all time.

Yorkshire skipper Anthony McGrath had erred on the side of caution by allowing his side to bat on for 20 minutes at the start of the day, adding 34 runs before declaring on 363 for five.

Somerset were up for the challenge from the start as Suppiah and Marcus Trescothick, who fell just four short of a second century in the match, put together an opening stand of 187 in 42 overs. But it was Tregor's amazing onslaught of nine sixes and six fours which finally broke Yorkshire hearts.

Trescothick played superbly for his 96, off 117 balls, with 15 fours and a six, and was unlucky to be out when he played on attempting to leave a ball from Matthew Hoggard.

By then it was a real contest. The score had progressed to 246 when Suppiah, whose only previous Championship century was his 123 against Derbyshire at Derby in 2005, had a swing at off-spinner Azeem Rafiq and top-edged a catch to McGrath at mid-wicket.

The Malaysian-born opener had faced 175 balls and hit 14 fours and two sixes. Incredibly, his departure saw Somerset turn up the heat by sending in tall pace bowler David Stiff, a former Yorkshire player, as a pinch-hitter.

Stiff responded with four mighty sixes and four fours in scoring 49 off 32 balls. But when he fell to Hoggard with the total on 307 for four and big-hitting Craig Kieswetter could manage only 17 before being bowled stepping back to cut Rafiq, it seemed Somerset would fall short.

Skipper Justin Langer was content to work the ball around while his partners went for the big hits. And it was Trego, coming in at seven, who succeeded in the most spectacular manner. He scored 42 of his runs in the space of 11 balls as he took 17 off five deliveries from Rafiq and then 24 of an over from Ajmal Shahzad.

Suddenly, Somerset needed only five an over from the last nine. But, despite the loss of Langer, Trego went on swinging from the hip to record the fastest first- class century of the season. Zander de Bruyn hit the winning boundary – and within minutes the heavens opened.

Match-winner Trego said: "That was probably the innings of my life, up there as good as anything I have ever done."

What was he thinking about when he walked out to the wicket? "To be fair I haven't had a great deal of runs with the red ball," he replied, "so when I went out there initially it was really just about survival, and then their bowler Shahzad gave me a few verbals and I thought: 'Right, I am going to after you here', and the ball turned from a pea to a balloon.

"It literally happened that quickly, and I don't have any explanation for it. When I first went in, it was just about survival, but once I started getting going the captain made me aware that, if I was in at the end, we were going to win the game, and that realization that I could do that made me focus even more.

"I know that there were sixes and fours flying about, but I don't think that I was taking any great risks, because I was taking the responsibility to be there at the end and we could chase whatever in the last few overs. I didn't think we were going to do it so quickly, and all I was trying to do was to hit the ball straight and true as possible and it was coming off."

Trego added: "This was a really important innings for me in my career because, although I have had a good average the last couple of years, I haven't scored many hundreds, but this one had real meaning. To get a hundred that wins means so much, and is a great day for the team."

Langer said: "It's a great tribute to the team to chase that sort of total and get it. Marcus Trescothick has scored 800 runs in the Championship and the way that he is batting is sublime.

"It is just unbelievable to have someone like that opening, and I'm really pleased for Arul Suppiah because it is his first hundred in four or five years. He works so hard and hopefully that will be a real turning point for him in his career.

"The way Pete Trego batted was superb and unbelievable," Langer added. "In the past he might have thrown that away, but he got to a point where he takes his cricket a little more seriously. If he took his cricket more seriously, he could easily play international cricket."

Earlier in the day, Somerset announced that they had extended Stiff's contract until the end of 2010. Langer said: "The fact that we have played him in six of the seven games shows that he is very good."