The Hornets found themselves two goals down at the break, but they dug themselves out of that hole in sensational style with a devastating seven-goal showing after the break as Troy Deeny, Matej Vydra and Gabriele Angella also joined in the home side’s free-scoring run following last week’s 5-0 win over Charlton Athletic.
Blackpool came into the game still searching for a first away win of the season, but they started the brighter and were rewarded with the opening goal in the eighth minute, although it came about largely due to their opponents’ defensive shortcomings.
Juan Carlos Paredes, who was under pressure from Ishmael Miller, got involved in a mix-up with Heurelho Gomes, with the ball ricocheting off the goalkeeper’s body and back to Andrea Orlandi, who kept his composure to fire home.
The Hornets, who had already gone close through an Angella header, missed a good chance to equalise soon after when Vydra put the ball wide from close range after good link-up play with fellow strikers Ighalo and Deeney.
Thereafter, Watford controlled possession and territory for the most part as they probed to get back on terms. Goalkeeper Elliot Parish was extended a couple of times by strikes from Ikechi Anya and Ighalo, but the visitors were defending resolutely, remaining organised and three minutes before the break they went 2-0 up.
The Hornets failed to react as David Ferguson attacked the right side of the penalty area before cutting inside and hitting a low cross-shot which wasn’t dealt with, Steve Davies made a real hash of his first effort but he still had the time to recompose himself and fire the ball into the back of the net.
It is fair to assume Hornets head coach Slavisa Jokanovic had some harsh words for his side at the interval but it is also reasonable to suggest he did not expect the reaction he got.
Within seven second-half minutes, the home side were back on terms as Ighalo tapped home a Miguel Layun centre from close range in the 47th minute before Deeney equalised five minutes later when he glanced home a Daniel Tozser corner.
And before the hour was up, Watford were incredibly 4-2 as Ighalo put his side ahead for the first time after a Layun cross was knocked down by Deeney and then Vydra made it 4-2, firing home an Anya cross was knocked down into his path.
Blackpool were utterly shell-shocked and in the 66th minute they conceded a fifth, Angella applying the finish after a Deeney header from a corner rebounded off a post.
Again an assist from the woodwork following a Deeney strike allowed Ighalo to complete his hat-trick in the 77th minute as the ball cannoned into the net off his chest.
And four minutes later the Nigerian had his fourth, with Watford’s latest close-range finish following more good work by strike partner Deeney.