Sussex coach Mark Robinson was left to reflect on slender margins after Sussex lost by 13 runs to Gloucestershire in the NatWest T20 Blast at Bristol.

A match reduced to 15 overs per side due to rain saw the hosts make 138-7 after losing the toss, Ian Cockbain hitting four fours and three sixes in his 52.

Sussex captain Chris Nash’s decision to field first with more rain threatening backfired as his side ended up batting in near darkness as they were bowled out for 125 in the final over.

The result took Gloucestershire, who began the campaign with a two-point deduction, level with Sussex on eight points with both counties in striking distance of fourth place in the South Division.

Gloucestershire’s score was built on a second-wicket stand of 69 in seven overs between Cockbain and skipper Alex Gidman. Yasir Arafat and Will Beer claimed two wickets apiece while Chris Liddle was the most economical Sussex bowler.

Sussex suffered an early setback in their run chase when Luke Wright was caught behind for a duck by trialist wicketkeeper Adam Rouse.

With the light fading, the visitors looked to face a stiff task and it got more difficult when Luke Wells fell for three in the second over.

Nash responded with four, four, six at the start of Gidman’s second over but fell for 25 when cutting Payne straight to Cockbain at point in the fifth and final over of power play, with Sussex on 47-3.

Matt Machan kept Sussex up with the required rate with 28 off 19 balls, then Ben Brown (19) and Beer did their best in now dark conditions.

Sixteen were needed off the last over from Jack Taylor but Beer was brilliantly caught on the boundary by Hamish Marshall at full stretch above his head for 18 to end Sussex hopes.

Robinson said: “T20 is a game that is often decided by inches.

“If Marshall had touched the boundary it would have been six and we would still have had a chance. It was so dark at the end but T20 is all about entertainment and we have just lost an excellent game of cricket.”