The former Fulham man has had to make do with sitting on the bench for much of the campaign and certainly grabbed his opportunity, giving Matthew Clarke and Christian Burgess no time to breathe and proving an effective outlet throughout the 90 minutes.

"Matt's been very patient and not had many opportunities in the last couple of months," said McClaren.

"He's come on in games, had a good impact and caused opponents problems. He deserved his opportunity and took it very well. I thought he was a constant threat.

"I said at the end of the window I'm delighted with the squad that I've got. We didn't make any signings, but we kept players and Matt Smith was one that we wanted to keep.

"It's great for him to get 90 minutes under his belt and score a goal."

The importance of this fixture was not lost on the former Middlesbrough manager, with the home faithful having had precious little to cheer in this competition since Trevor Sinclair's memorable overhead kick against Barnsley in 1997.

Looking ahead, the 57-year-old was bullish about his team's chances against the Hornets.

He added: "Anything can happen in the FA Cup. We're at home, it's on a Friday night under the lights, it's on TV. It's an opportunity for certain individuals and the team to show themselves against Premier League opponents.

"Watford are very strong and we'll have to put a top performance in to get any kind of result."

Portsmouth boss Kenny Jackett was magnanimous in defeat and while praising his team's character, he was rueful about the goals that were given away.

Jackett said: "I thought it was a spirited performance, but we conceded three set-pieces across the two games. At times we moved the ball well, but for the majority of the game couldn't find the shots to trouble QPR.

"We can't have any complaints. We've given some good sides a run for their money in this competition."

Jackett singled out lone striker Ollie Hawkins for praise, who played for the first time since New Year's Day.

The 26-year-old had a thankless task, but showed intelligence to bring the onrushing midfielders into the game, even if he wasn't able to take any shots in anger at Joe Lumley's goal.

"He was a good outlet for us. It's good to have him back, as he's a very effective player and we just have to make sure we have options running off him," Jackett said.

Attention now return to League One, as Pompey aim to arrest a four-game winless run when they travel to Plymouth on Saturday.

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