Somerset 353 for 5 (Trego 141, Azhar 110, Siddle 4-60) beat Essex 154 for 6 (Lawrence 51, Groenewald 3-34) by 36 runs (DLS method)
Azhar Ali and Peter Trego hit chanceless centuries as Somerset maintained their impressive start to the season with a 36-run Royal London One-Day Cup win over Essex under Duckworth-Lewis-Stern at Taunton.
The pair added 217 for the second wicket, a Somerset record for any wicket in List A games against Essex, Azhar hitting 110 and Trego contributing 141 to a total of 353 for 5 after their team had been invited to bat first in a contest reduced to 39 overs per side.
Essex had reached 82 for 3 from 12 overs in reply when rain forced a lengthy stoppage. When the teams went back on at 8.25pm, their target had become a further 109 from five overs and they fell 37 short.
The result gave Somerset maximum points from four group matches, while for Essex it was a third defeat in four. Azhar's hundred was his 17th in List A cricket and Trego's his tenth.
The game got underway at 3pm, two hours after the scheduled start, because of rain. There was no hint of the run-feast to come when Siddle struck in the second over, Tom Banton skying a catch to cover.
Somerset's new floodlights were on from the start. Azhar and Trego began cautiously until the latter cut loose in the seventh over, pulling a six over midwicket off Sam Cook and then lofting him over long-on into the River Tone.
Azhar was first to his half-century, off 45 balls, his innings characterised by some wristy off-side shots. The century stand came up off 88 deliveries and Trego brought up his fifty with a straight six off Simon Harmer, having faced 46 balls.
The two batsmen, with a combined age of 71, showed all their experience in shot selection, never looking in any bother. Azhar's first List A century for Somerset and first for the county at Taunton in any competition was reached with a six over extra-cover off Matt Quinn.
The former Pakistan ODI captain had faced 84 balls, hitting nine fours and four sixes. Trego went to three figures in the following over off 84 deliveries, with eight fours and four sixes, celebrating as extravagantly as if it had been his first ton.
By the time Azhar was caught at long-on off Paul Walter, Somerset were well on course for a winning total. Trego went on to fall six short of his career-best List A score, while Lewis Gregory and James Hildreth cemented their side's strong position.
After five balls of the Essex innings, a shower sent the players back to the dressing rooms. The visitors, on 4 without loss, faced a revised target of 311 off 33 overs when play resumed at 6.35pm and quickly lost Walter, caught behind down the leg-side off Josh Davey for 1.
Alastair Cook survived a sharp chance to Lewis Gregory at midwicket on 15 before falling to Craig Overton's next delivery, wicketkeeper Banton taking a second catch off a thin edge. Tom Westley took 14 off an over from slow left-armer Roelof van der Merwe. But when the tenth over was completed, the number required to constitute a game, Essex were on 71 for 2, 34 behind on DLS.
Westley was bowled trying to lift van der Merwe over the leg side and it was raining steadily as he walked off. Shortly afterwards the clouds gathered and the umpires called another halt, with Dan Lawrence unbeaten on 32.
Another restart was ordered for 8.25pm. With only a sprinkling of spectators left in the ground, Essex, needing more than 21 an over for the target of 191, added 72 to close on 154 for 6, Lawrence being dismissed for 51.
During the interval Somerset made a presentation to Hildreth, who was making his 625th appearance for them in all competitions, the most by any player in the club's history.