Somerset opener Josh Thomas, 21, continued his good form with a third century of the season Rothesay County Championship, Division One, Uptonsteel Grace Road, Leicester (day one) Somerset 354-9: Thomas 100, Lammonby 74; J Rew 52*, Gilchrist 2-65; A Patel 2-80, Mike 2-109 Leicestershire: Yet to bat Somerset 3pts Leicestershire 3pts

Josh Thomas continued his impressive season at the top of the Somerset batting order as the Division One leaders did their best to further darken the mood of relegation-threatened Leicestershire on day one at the Uptonsteel County Ground. The 21-year-old left-hander batted superbly for his third century of the season, sharing a 181-run opening stand with fellow left-hander Tom Lammonby (74) against a makeshift Leicestershire seam attack.

Nonetheless, on a day that saw the first session lost to the weather, it could have been worse for the home side, who fought back to claim full bowling bonus points with nine wickets after tea. Somerset closed on 354-9 after being asked to bat first. Nathan Gilchrist, who arrived on loan from Warwickshire on Monday, has 2-65. Somerset also bagged three more points, James Rew contributing a valuable unbeaten 52.

Leicestershire charged over Grace Road pitch Still in the bottom two in the table despite an upturn in form, Leicestershire need fortune to favour them after learning before play began that they had been charged with breaching ECB regulations over what was deemed a sub-standard pitch prepared for last month's win over Glamorgan at Grace Road. They face losing all of the 19 points gained from that match if their appeal fails, which would make keeping their place in Division One after being promoted as Division Two champions extremely difficult with only two rounds left after this one.

By contrast, optimism is running high for Somerset as they seek to win cricket's premier red-ball competition for the first time in their history, having moved into top spot with an innings' victory over Glamorgan last week.

On a green pitch, with plenty of cloud cover lingering, Somerset might have faced a trickier first session, but a home attack lacking its top two wicket-takers in Ben Green and regular captain Ian Holland and with three other seamers sidelined, was rarely able to inhibit Somerset's progress. Gilchrist, an 11th hour arrival before the window for loan signings closed, joined Ben Mike in taking the new ball, but neither could do much with it. Offered too many wide or overpitched deliveries, Thomas and Lammonby both profited handsomely from their cuts and drives, putting on 173 in the 33 overs up to tea.

Leicestershire bowled better in the final session, spurred on when Lammonby departed three overs in, lofting a catch to wide third man off Alex Green with a strangely miscued late cut. Archie Vaughan's ambition to improve his own numbers after a season of modest returns was short lived. He had made only 21 when Gilchrist had him leg before.

Then Thomas, who pulled Mike for a meaty 15th four and took a single to be 100 from 152 deliveries, shouldered arms to a ball in Mike's next over that came back to hit his off stump, out without addition. Nonetheless, his innings confirmed the impression made in hundreds against Yorkshire and Essex among 760 red-ball runs so far this season that he has the talent to go far. He looked a much different player, certainly, than the one who had a loan spell at Grace Road last season as back-up left-arm spinner in the Vitality Blast, batting at No 10.

Leicestershire picked up a bonus wicket when New Zealand Test batter Henry Nicholls was run out after a mix-up with Rew before Mike picked up his second as Craig Overton edged a catch to Jonny Tattersall, keeping wicket as substitute fielder for Ben Cox, who had left the field, feeling unwell. Gregory was out somewhat tamely, caught at short fine leg, before New Zealand left-arm spinner Ajaz Patel, finding some turn, had Jack Leach leg before. The fall of late wickets continued with Migael Pretorius beaten and bowled by Rehan Ahmed.

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