Roffey skipper Matt Davies said: “Obviously it is very disappointing to lose a game we had in our grasp.
"Nonetheless we put in good performances and there were lots of positives to take from the match.”
A promising Roffey start gave way to 45-3, before Rohit Jagota made a run a ball 57 and, with consistent Davies – finishing unbeaten on 45 – combined to put on 77 for the fourth wicket.
Later batsmen went cheaply, but 160-6 from 35 overs presented a demanding target in the conditions, with Ben Twine and Joe Pocklington taking two wickets apiece.
Then, when Jagota accounted for Sussex signing Alastair Orr and Leigh Harrison dismissed wicketkeeper Oli Carter, the hosts were stuttering at 15-2.
Enter the highly promising Lenham brothers, Archie and Scott, whose father Neil and grandfather Les had been such stalwarts for the county with nearly 700 matches, over 26,000 runs and useful wickets between them.
But, this time both brothers perished in another superb spell from Harnoop Kalsi, Davies stumping Archie and catching Scott.
With Eastbourne teetering on 68-6, it appeared to be Roffey’s day – until Twine and Pocklington produced a stand of 66.
Yet, at 134-7 with Twine gone for 37 and 27 required off the last five overs, Roffey entertained hopes.
Pocklington was subsequently trapped lbw for a pugnacious 42, including fice sixes, Roffey clawing back with 12 needed from the last two overs and eight wickets down, but a four and a six from Chris Borsoi saw Eastbourne home with five balls remaining.
A full scorecard from the game can be found here.
Davies added: “Eastbourne are a great side and will certainly be up there at the end of the season – they’ve got a great group of young players.
"Rohit batted very well to get us to a competitive total if we bowled well and Harnoop Kalsi was outstanding, putting us in a position of strength, but sadly we couldn’t get over the line.
"We’re top of the league and have put in two good performances to start the season – it’s not all doom and gloom!”
Kalsi took 4-14 from his seven over allocation and said: “In the rain it was difficult to tell whether 160 was a winning score.
"But, bowling at the right pace on that wicket made it hard for batsmen to settle, and I thought we’d done enough to win.”
Roffey’s scheduled National Cup game versus Reigate CC was rained off on Sunday.
There is a big home weekend at Roffey coming up, with, on Saturday, a league match against much fancied East Grinstead CC (who were surprisingly bowled out for just 134 last Saturday to be overwhelmed by Preston Nomads CC), with the Reigate match rearranged for Sunday.