|Harlequins (10) 20|
|Tries: Dombrandt, Saili Cons: Smith, Long Pens: Smith 2|
|Newcastle Falcons (0) 7|
|Tries: Davidson Cons: Flood|
Harlequins piled more Premiership pain on bottom side Newcastle Falcons with a hard-fought victory at The Stoop.
An intercept try from Alex Dombrandt and penalty from Marcus Smith put Harlequins 10-0 up at the break.
A second Smith penalty and try from Francis Saili sealed Quins' second league win at home this season.
Andrew Davidson's try in response was not enough as Falcons' five-match unbeaten run in all competitions came to an end.
Newcastle's sixth league defeat of the season comes after an impressive resurgence, which has seen them beat French giants Toulon and Montpellier to top their European Champions Cup group after two games.
With Mark Wilson remaining with Eddie Jones' England side and five other Falcons also on international duty, the trio of Pedro Bettencourt, Davidson and John Hardie were handed their top-flight debuts after featuring in recent Premiership Cup wins.
Quins, who were without the England pair of Danny Care and Kyle Sinckler but had Mike Brown, Nathan Earle and Joe Marchant start on their return from the Red Rose camp, were made to toil by a Newcastle side that was forced to make a number of early changes.
The competition strugglers had fly-half Joel Hodgson leave the field on a stretcher in the 10th minute, having also lost centre Johnny Williams to injury before kick-off.
The first points of a tight contest took 22 minutes to come, with Smith putting the hosts ahead with a penalty.
And just as Newcastle pressed for a response late in the first half Dombrandt added to the lead by picking off a pass and racing over unopposed.
Even with Quins a man down following Lewis Boyce's yellow card for infringing at the scrum, the hosts managed to add to their advantage thanks to Smith's boot.
The match failed to hit any great heights, and the result was assured by the time Davidson hit back for Falcons.
Harlequins head of rugby Paul Gustard:
"I enjoyed the fact we won, we needed that tonight. We were the dominant team by a long way and we were courageous.
"We kept the ball in slippery and wet conditions, it was a very good performance. Unfortunately, we did not break them down as much as we would have liked to and that was partly because of our accuracy and partly because they refused to roll away at the breakdown.
"I was really happy in the first half but just frustrated we did not score more points. It was a missed opportunity. In the second half, the game lost momentum and we were grinding it out."
Newcastle Falcons director of rugby Dean Richards:
"I think we lacked a lot of accuracy in the first half and it came back to haunt us. I don't think Quins were much better than us.
"It came down to who was playing in the right areas, but sadly we weren't. We cannot play with the same inaccuracies and, if we do, we lose.
"We don't want to lose next week and we are not prepared to do that, so we have a lot to look at."
Harlequins: Morris; Earle, Marchant, Tapuai, Brown; Smith, Mulchrone; Boyce, Elia, Collier, Symons, Merrick, Dombrandt, Clifford, Chisholm.
Replacements: Crumpton, Marler, Swainston, Glynn, Ward, Lewis, Lang, Saili.
Newcastle: Hammersley; Tait, Bettencourt, Flood, Sinoti; Hodgson, M Young; Lockwood, McGuigan, Welsh, Green, Davidson, Graham, Hardie, Chick.
Replacements: Cooper, Davison, Wilson, G Young, Burrows, Stuart, Swiel, Stevenson.
Referee: JP Doyle.