Jack Leach, the Somerset left-arm spinner, has been left out of the England Lions team for the first unofficial Test against Sri Lanka A in Pallekele after struggling with his new bowling action.

Leach, the second-highest wicket-taker in Division One of the County Championship in 2016 with 65 at 21.88, was thought by some to be unfortunate not to win selection in the England Test squad that toured Bangladesh and India. But his action was found to be illegal during routine tests at the national performance centre in Loughborough after the season and he was obliged to remodel it before departing on tour.

While Leach initially thought the remedial work had gone well, the pressure of playing in a match situation and for a national side appears to have exposed some unfamiliarity with the new action. He conceded 68 in 14 wicketless overs in the second-innings of the warm-up match against the Sri Lanka Board President's XI - the other specialist spinner, Ollie Rayner, took 3 for 55 from 22 overs by comparison - which led to the tour management going into the unofficial Test with Rayner as the only specialist spinner. Tom Westley and Liam Livingstone will provide spin back-up as required.

The Lions management have stressed that there is no suggestion Leach has been left out due to any fears of illegality with his new action. It is, they say, to provide him more time to groove it in the nets before testing it under the pressure of a match situation. He has not been ruled out of the second match in Dambulla.

While a period of readjustment was probably inevitable for Leach, it may be worth noting his county captain's views towards the end of the season. Chris Rogers suggested Leach "emotionally… still has a bit of a way to go", and suggested he may not quite be ready for international cricket where "the challenges… are a lot more difficult."

The ECB is also painfully aware of the case of another left-arm spinner, Simon Kerrigan, who endured a chastening Test debut at The Oval in 2013 and has never fully recovered. England are keen to ensure Leach has a more robust action and, as a consequence, a more robust sense of confidence, before he is thrust into relatively high-pressure situations.