A single goal from Britt Assombalonga gave Watford Under-21s only their third Professional Development League South win of the season at Vicarage Road this afternoon.

The striker was one of a number of more senior players that coach Omer Riza was able to field, and it was probably that dusting of experience which made the difference.

Rangers must feel they’ve been unlucky to twice face a Watford Under-21 side that has included a sprinkling of players with first-team experience.

When Watford won the away game 4-2 in October their starting XI featured Mattie Pollock, Joseph Hungbo, Tom Dele-Bashiru, Vakoun Bayo, Yaser Asprilla and Samuel Kalu

Indeed, of the three league wins this season, two of them have been against Rangers.

Christian Kabasele played in defence while James Morris captained the team at left wing-back.

Over on the opposite side of the pitch there was a welcome return to action for Joao Ferreira, who has been sidelined with a hamstring injury.

The Portuguese looked very much at home in the right wing-back role, happy to bomb on down the flank or cut inside and run at the visitors’ defence, much as he did when he scored for the first team recently.

With Jeremy Ngakia and Mario Gaspar already there, the Hornets now have three options to play on the right – from famine to feast, given Dan Gosling had to fill in there earlier in the campaign.

Watford should have possibly won more comfortably than they did, certainly based on the chances created. The goal they did score was either a superb piece of play to spring an attempt at an offside trap, or a howler from the linesman - in the build-up Ferreira was played in so far behind the Rangers defence it had to be one or the other.

In midfield Jordan Fankwe had a solid game, snapping into tackles and covering a lot of ground while Adrian Blake was his usual self – a bag of tricks who can spin off defenders, run past them at pace or simply drop a shoulder and create a yard of space.

After seven minutes Watford were caught playing out form the back and when Steven Bala robbed the ball 30 yards out he attacked the box and then sent a low shot wide.

Six minutes later Blake broke from inside his own half, carried the ball 30 yards and slid it to Assombalonga on his left. The striker moved into the box and tried to find the incoming Ferreira but his low cross was blocked.

The giant Kargbo was unsurprisingly the target of QPR set plays, and he barely had to jump to meet a cross in the 18th minute, but his downward header was comfortably held by Macaulay.

The Hornets had a great chance in the 20th minute when Kabasele’s long ball totally cleared the Rangers defence and sent Ferreira clear into the box in the inside-right channel. The angle was on the tight side but the wing-back should have done better than send his shot straight at Salamon.

Watford scored the game’s only goal in the 29th minute when Grieves sprung QPR’s attempt to play a high line and released Ferreira into the box on the right. He steadied himself and squared for Assombalonga to poke the ball past Salamon.

Four minutes later a Watford attack was only partially cleared and Blake met the loose ball with a first-time shot that beat Salamon but crashed off the far post.

Just after the hour a clever back-heel from Blake sent Assombalonga racing away through the middle but Woodman did very well to cover across and block as the striker tried to get his shot away.

Three of the senior players were taken off after 66 minutes with Kabasele, Ferreira and Assombalonga replaced by Coyne, Delyfer and Adeyemo.

Shortly after Grieves did well to drag a low pass back from the by-line but Fankwe met the ball and pulled his shot wide.

Seconds later Grieves – back after a calf injury - drove into the left of the box and slipped a pass to Blake. He attacked the near post and then flicked a cross which Adeyemo stabbed against the upright.

With ten minutes to go a nice piece of skill from Blake just inside the box allowed him to tee up Grieves for a shot from an angle on the right of the box that Salomon smothered.

Macaulay’s first real save of the second half wasn’t required until the 86th minute, but it was a very good one. Pedder drove from left to right and then moved into the box, unleashing a fierce shot that the Watford keeper pushed away at full-stretch, and Anthony put his follow-up effort wide.

Watford U21s: Macaulay, Ferreira (Delyfer 66), Morris, Kabasele (Coyne 66), Holding, Andrews, Grieves (Touray 88), Fankwe, Assombalonga (Adeyemo 66), Blake, Manning. Sub not used: Ortelli