Walter Mazzarri heeded the harsh lessons of Watford's FA Cup loss to League One Milwall as the Hornets claimed a famous 2-1 win over Arsenal at Emirates Stadium.
The Italian's position had come under growing scrutiny following Sunday's 1-0 loss at The Den, but the response from his side on Tuesday was emphatic.
Watford were two goals ahead inside 13 minutes through Younes Kaboul and Troy Deeney, and dug deep to repel wave after wave of Arsenal attacks following Alex Iwobi's second-half strike.
"I had to take some decisions on the game and formation after the Millwall defeat and we had to play differently, which showed with our performance," Mazzarri, whose side were winless in seven league games, said in quotes reported by BBC Sport.
"We played a great first half and the condition of some of the players is returning. In the second half, Arsenal managed to press us but in general it was very well done.
"Against a great team in their stadium, you cannot allow them to play too much of the ball and you have to press them. We did that very well but you cannot do it for 90 minutes. That was our tactic."
It was confirmed before the match that Odion Ighalo had completed a big-money switch to Chinese Super League club Changchun Yatai.
The Nigeria international scored 15 Premier League goals last season, having helped fire Watford to promotion in the previous campaign, but his form faded badly in 2016-17, with just one top-flight goal in 18 outings.
Mazzarri added: "I want to wish Odion Ighalo good luck because he is a great player and professional. I am very happy with our January signings in M'Baye Niang and Mauro Zarate and I have to do the best with that."
Deeney, who netted his sixth top-flight goal of the campaign, paid tribute to former Watford manager Graham Taylor, who passed away this month.
"It is Graham Taylor's funeral [on Wednesday] so I think all the players and fans would like to dedicate this result to his family," he said.
