Tom Haines’ unbeaten 89 and a half-century from opening partner Dan Hughes put Sussex in control on a rain-shortened first day against Surrey at the 1st Central County Ground.
Rain arrived just after 15:00 BST and although they returned at 17:40, only 11 more balls were possible.
Sussex closed on 227-2 from 53 overs, Haines and Hughes having laid the platform with a first-wicket stand of 102 after Sussex had won the toss.
For the champions’ attack it was a tough day.
Gus Atkinson bowled some overs in a second-team friendly earlier in the week, but this was his first competitive outing since England’s Test series against India in February and he understandably looked rusty, especially in his first spell when he struggled with the Hove slope, overstepping six times and conceding 53 in 10 wicketless overs either side of lunch.
Atkinson came in for Kemar Roach while Jamie Smith, rested by England, was replaced by 20-year-old left-hander Ollie Sykes.
Atkinson returned for a second spell at the sea end but bowled just one more over before the rain got too heavy and umpires Ben Debenham, who was standing in his 100th first-class match, and Paul Pollard took the players off for the first time.
It is the first time these teams have met in the Championship at Hove for 15 years and although as usual there was a good covering of grass on the wicket there were few demons in the pitch for Haines and Hughes, who progressed at five runs an over, and little assistance through the air.
Rory Burns rotated his seamers but had turned to leg-spinner Dan Lawrence after 55 minutes, with Dan Worrall’s opening four overs going for 29 as the Sussex left-handers feasted on any width and enjoyed a short boundary on the scoreboard side.
Hughes needed just 47 balls to reach his fifty and had progressed serenely to 62 when he drove a length ball from Matthew Fisher back at the bowler and Fisher took a good two-handed catch in his follow through.
Lawrence struck three overs later when a quicker ball deceived Tom Clark who was pinned in front trying to work the ball into the leg side. Surrey sensed a breakthrough but Haines and Alsop, who was unbeaten on 39 at stumps, regrouped.
After lunch Surrey bowled aggressive lengths in an attempt to unsettle the two left-handers and Alsop was hit on the side of the helmet when he ducked into one Worrall bouncer while a short ball from Atkinson deflected off Haines’ helmet and flew down to the third man boundary.
But with relatively little pace in the wicket the batters grew in confidence whenever Worrall or Atkinson pitched short, and Haines hooked Worrall impressively to bring up his half-century with a boundary. When Atkinson returned for his second spell he posted two fine legs, a fly slip and no conventional slips.
Fisher had been the pick of Surrey’s attack with 1-17 from eight overs and he beat the bat several times, but Haines and Alsop persevered and by stumps their stand was worth 125 from 31 overs.
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