"Whether we can catch Watford is just up to us to keep performing like we have done today," said the Dane.

"We're creating chances, and of course we're very dangerous going forward.

"It's all about us to keep performing and we'll see where that takes us, but it is for Watford to lose though now.

"There's no mind games between us or anything like that, but they're in sync right now and it's going to be difficult to catch them.

"We'll just do what we can in these last six games."

The visitors hit the front after nine minutes when Bryan Mbeumo side-footed past Daniel Iversen from eight yards.

Then it was two when Finnish frontman Marcus Forss finished off another Mads Roerslev cross for his ninth goal of the season.

Tarique Fosu and Vitaly Janelt both came close as Preston were overrun by Brentford's fluid attacking movement.

The third would not come until 75 minutes had gone when Ivan Toney sealed the spoils, nonchalantly nodding goal number 29 of the season past Iversen from a couple of yards out.

Toney then turned provider for substitute Sergi Canos to make it four from close range in the 82nd minute.

Fellow substitute Emiliano Marcondes' calm finish from a tight angle in added time wrapped up a dream day for the Bees.

Frank said: "Right from the off we played some really good football, we scored two good goals in the first half, and they gave us a great platform.

"We had to defend well of course, but we're always capable of doing that. After we got our third goal we were in very good control.

"In recent weeks we have been lacking a really top performance, but I definitely thought we got that today."

Preston failed to land a blow on the promotion chasers and have now won one of their last eight league contests, with interim manager Frankie McAvoy taking responsibility for a tactical switch that backfired.

"I didn't think there was too much difference between the two sides in the first half, but they showed their quality with a couple of clinical finishes," McAvoy said.

"Overall we haven't defended well enough today, though, and that was disappointing.

"I decided to make a few changes and went with three up top, but clearly that didn't work and that's down to me.

"Their third goal was a killer for us. We'd gone a little bit gung-ho, but that's just not happened for us and we've been punished.

"We tried to get back into it in the second half, but it's backfired on us.

"After a couple of decent results last weekend this has been a really harsh lesson for everyone.

"The important thing is that we learn as much as we can from this result and move on to next week."