.The visitors led by 17 points at half-time and stretched their lead to 29-7 before Bromley – who had lost each of their opening six games – began to nibble away at the deficit.
The hosts might have snatched a dramatic win had they not missed a last-minute penalty but Deal coach Dave Wiggins said it would have been a travesty if his team had lost.
He added: “There were nine tries in the game and seven of them were scored down the slope which tells you what sort of game it was.
“Credit to Bromley, they ran at us constantly in the second half but again our defence got us through.
“The last five minutes were a bit nervy but we kept our heads and defended well.”
Ongoing refurbishment work at Bromley’s ground meant the teams had to change across the road at Park House but despite that, the Lions were quickly into their stride, with Argentinian Juan Bautista Vila scoring the opening try, picking up after Bromley had been pushed off their own ball to sprint over.
The second try came from Joe Hinkins and with Connor Moss adding both conversions, the visitors moved 14-0 ahead.
A third try, from Lenny Brown, made it 19-0 and after Bromley had responded with a converted try, Danny Bushell went over to see Deal deservedly ahead 24-7 at the
break.
Bautista Vila’s second try, early in the second half, left Bromley with a lot of work to do but prompted by their impressive scrum-half, they pinned Deal back, scoring three tries to claim a losing bonus point.
Sam Cook, up from the second XV, performed well on his debut in the second row, while 17-year-old Henry Evans came off the bench to play on the right-wing in a re-shuffle caused by a shoulder injury to No.10 Moss.
The Lions, in ninth, host fourth-placed Charlton Park at the Drill Field on Saturday (start 2.30pm) and Wiggins expects another close contest.
He added: “Charlton Park are always tough opposition but I don’t think we’ve got anything to fear from anyone at home.”