American Patrick Tallent set up the chance to complete a rare double with a second round three-under-par 68 in the Seniors Amateur Championship at Royal County Down.
With the Championship having been blighted by rain delays on day one, eight groups had still to complete round two when play was halted due to darkness on Thursday at 8.40pm.
But Tallent was safely in the clubhouse on one-over-par 143, two shots ahead of fellow Virginian, Matthew Sughrue, with Portmarnock's Adrian Morrow another three shots back in third place on 148.
Still on the course, the nearest threat to the leaders was American John McClure, who tied for third at Ganton last year. He was on eight-over-par for the Championship with six holes of the second round still to play.
Winner of the US Senior Amateur Championship at Big Canyon in California last September, it was a long day for Tallent, who comes from Vienna, Virginia.
Caught up in the first round overnight suspension, he completed 11 holes of his first round 75 before heading back out to post the first sub-par score of the Championship.
With five birdies he seemed set to take even firmer control, but he slipped up with two penalty shots in a double-bogey seven at the final hole. He had to take a drop from a bush beside a bunker and then hit into gorse and was again unplayable.
"Apart from that, it was a really good round," said the former basketball player who worked in the world of finance before retirement. "I hit the ball close all day and the longest birdie putt was from about ten feet at the first."
Tallent played in the final two-ball in the last round of the Championship at Royal Aberdeen two years ago, but was caught out by a torrential rain storm and finished tied seventh. He was also in the top ten 12 months ago.
Sughrue is a newcomer to Seniors golf, but the 55-year-old from Arlington has already made his mark by beating the professionals and winning the Maryland Senior Open.
He only played three holes of his first round on the first day. But, after the overnight suspension, he woke up to sunshine, made his move with an eagle at the 12th and shared the first round lead with Morrow on 74.
Sughrue's second round 71 was a model of consistency with a bogey at the 11th being erased by a birdie from ten feet at the 16th.
Having recently retrained as a psychotherapist, he is enjoying the new phase in his life. "I missed a few makeable putts today but it was a good solid round," he said.
The two players at the head of the leaderboard both had the advantage of using local caddies. Tallent had the experienced Roger Sharp on the bag and Sughrue hired 15-year-old schoolboy, Fintan Canavan.
Morrow, a former European and Irish Senior Champion, provided an Irish flavour to proceedings. He shot two rounds of 74 and could have finished closer to the two leaders if he hadn't dropped shots at the 16th and 17th in the second round.
Martin Galway, from Brighton and Hove, led the English challenge on eight-over-par 150. His second round 71 included a real purple patch of four birdies and an eagle in seven holes from the turn.
Brady Exber, the defending champion from Las Vegas, shot rounds of 80 and 79 and was 16 shots behind the leader but just inside the projected cut mark.
For full scoring from the Championship please click here.