Of all the results possible after the first day of this extraordinary game, a victory for the Red Rose seemed about as likely as three consecutive Mancunian days without lengthy rain delays.
But in the end we got both, with stand-in skipper Liam Livingstone and wicket keeper Alex Davies’ second innings centuries proving as vital as Ryan McLaren’s match figures of eight for 113 or the galvanising presence to the seam attack of James Anderson.
Lancs coach Glen Chapple was overjoyed with his side's comeback: "After the first innings the remainder of the game has been a sustained effort of determination, quality cricket and a team unit sticking together
"The lads are delighted and it's a fabulous way to win. It needs a remarkable effort from the batting unit and the partnership between Alex and Liam was of high quality. It was what was needed if we were going to have any chance.
"We know how pitches at Old Trafford can get if the sun gets on them but the level of application they showed was a fantastic effort and a hint at what can be achieved if you are determined enough."
Thanks to Livingstone and Davies’ third day heroics, the hosts began this final day with a lead of 254 runs and they had extended that to 295 all out by the time Lewis Gregory had dismissed the stubborn pair of McLaren for 45 and Steven Parry for 44 with Tim Groenewald accounting for Kyle Jarvis third ball for 0.
A short break for rain saw five overs lost from the day's play but with 77 overs to reach their target, Somerset faced the new ball pair of Anderson and Jarvis with some confidence.
Trescothick was dropped behind the stumps on six by a diving Alex Davies off Jarvis but Somerset went into the lunch break at 29-0 off 10 overs and with no warning of the carnage to follow.
What did develop was a devastating spell of bowling from the host’s seam attack which two hours laterhad left the visitors 107-7 at tea with the 188 runs required for victory looking an impossible task and the small matter of saving the game almost as unlikely.
Anderson was superb and the selectors will have no concerns regarding his form as he removed two former England teammates in the shape of Trescothick, who edged to McLaren for 36, and wicket keeper Steven Davies, bowled for three.
Aside from England’s record wicket taker, it was Jarvis who claimed the first dismissal when he pinned Dean Elgar, a century maker in the first innings, for eight, before McLaren, who had an outstanding match, accounted for Somerset captain Tom Abell without scoring, James Hildreth for 43 and James Davey for just two in the last over before tea.
While individual figures may have hinted at otherwise, this was a team performance from the bowlers and it was Jordan Clark, who weighed in with the wicket of Peter Trego, who really found his rhythm after tea.
Lewis Gregory was the first to go for four as Clark forced an edge to Livingstone at first slip, followed by Jack Leach, who betrayed his good batting in the first innings with an awful top edge to Haseeb Hameed at third man without scoring.
Groenewald provided the classic dénouement when he was castled by McLaren to spark wild celebrations and why not? After being bowled out for 109 in their first innings and conceding a lead of 169 this was the kind of victory that does not happen every day.
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