To use the vernacular, Jonás Gutiérrez’s goal celebration was pants.

For 15 months, the Newcastle United winger has kept a Spider-Man mask stuffed in his underwear ready to be worn in the event of him scoring; week after week, he has dribbled into the area and fallen over. When he finally broke his duck on Saturday, there was no mask, just mutiny.

Gutiérrez was cross. In fact, so was most of St James’ Park. The combination made for a vivid atmosphere, as supporters channelled their distaste for Mike Ashley into backing for their team and the players responded with a comprehensive victory. Specifically, Gutiérrez was annoyed with speculation linking him with a move to Roma. “I did not celebrate because of that,” the Argentina player said. “I have waited a long time to score, but I left the Spider-Man mask in the changing room. The only thing I’ve ever said is that I want to stay at Newcastle and get promotion.”

The grumpiness broke, because Gutiérrez was clearly born with a sunny disposition — “When I score my next goal, for sure I will take out the Spider-Man mask and I promise to wear it,” he said — but for the 22 minutes in which he was on the pitch (he departed with a muscle strain), he tore Peterborough ragged. His goal was the culmination of a superb run and was followed by a header from the impressive Andy Carroll and a left-foot lob by Danny Simpson. Just as Newcastle were irrepressible, Peterborough were abysmal, but after a brace of fine saves from Steve Harper, Dean Keates mustered a consolation.

On afternoons such as this, the power at Newcastle’s disposal, whether on or off the pitch, is obvious. More than 43,000 people were present at a stadium that the club’s owner has, on top of myriad other calamities — he has referred to his tenure as “catastrophic . . . I’ve lost my money and made terrible decisions,” — decided to rename. Extraordinary.

In the short term, of course, Ashley is not going anywhere, but with all the banners, songs and chanting, his existence cannot have felt comfortable. Nor did Peterborough’s. “What people will remember about today is the fact that we have great support,” Chris Hughton, the manager, said.

Newcastle United (4-4-2): S Harper — D Simpson, S Taylor, F Coloccini, J Enrique — D Guthrie, A Smith, K Nolan, J Gutiérrez (sub: R Taylor, 22min) — M Harewood (sub: N Ranger, 78), A Carroll 8 (sub: P Lovenkrands, 78). Substitutes not used: Gérémi, N Butt, T Krul, T Kadar.

Peterborough United (4-4-2): J Lewis — C Lee, R Bennett, C Morgan, T Rowe — C Whelpdale (sub: S Batt, 75), T Diagouraga (sub: P Coutts, 46), D Keates, D Rose (sub: A Mclean, 46) — G Boyd, C Mackail-Smith. Substitutes not used: B Amos, R Martin, G Zakuani, L Frecklington. Booked: Bennett.

Referee: A D’Urso. Attendance: 43,067.