Somerset seamer Alfonso Thomas became the first bowler in over a decade to take four wickets with four consecutive deliveries in an English first-class match on Tuesday.
Sussex were 33 without loss on the third day of four in a First Division County Championship match at Taunton when the 37-year-old Thomas sparked a collapse that saw the visitors lose five wickets in 10 balls without adding a single run.
Cape Town-born Thomas, whose sole international appearance came in a Twenty20 match for South Africa in 2007, began his brilliant burst by bowling James Anyon for 18 and next ball had Rory Hamilton-Brown lbw before former England batsman Ed Joyce was caught behind to complete the hat-trick at the end of the 17th over of the innings.
But if Sussex thought they were about to get some respite, they were mistaken as, four balls into the next over, Peter Trego dismissed Chris Nash with the help of a catch by James Hildreth.
Right-arm seamer Thomas returned and with the first ball of the subsequent over he bowled Matt Machan for a duck.
Thomas eventually finished the innings with with five for 40, his third five-wicket haul in three successive Championship matches at Taunton, as Sussex were bowled out for 178.
Somerset lost four wickets in their pursuit of a modest target of 104 before a six by Craig Kieswetter sealed a six-wicket win.
Victory left Somerset, who have never won the County Championship, on top of the table.
Thomas was the first Somerset bowler to take four wickets in four balls in first-class cricket. He was also the first bowler to do so at Taunton.
Thomas, who had considered retiring from red ball cricket and concentrating solely on limited-overs matches after a series of injuries, piad tribute to Brian Rose, the former Somerset director of cricket and captain, for persuading him to join the west country county in the winter of 2007/08.
"It was the shoulder, then it was the back, and you lie in bed at night and think 'Is this the end?'", Thomas told the Cricinfo website.
"This could be the year," Thomas said when asked about Somerset's title aspirations after a series of near-misses.
"I'm starting to believe. Taunton is home now for me and my family don't want to go anywhere.
"That was the first hat-trick of my professional career and has to be right up with the highlights.
"But yes, the turning point of my career came when a man called Brian Rose showed belief in me. I love Somerset."
Surrey's Gary Butcher was the last player to take four wickets in four balls in an English first-class match. against Derbyshire at The Oval in 2000.
The feat has now been performed on 40 occasions, with the most recent prior to Thomas's effort by New Zealand's Neil Wagner for Otago against Wellington at Queenstown in 2010/11 and Khalid Usman for Abbotabad against Karachi Blues at Karachi in a Pakistan domestic match in 2011/12.