Manchester United boss Jose Mourinho insisted he was too experienced to instigate a title-winning bandwagon despite his side beginning the season in scintillating style by obliterating West Ham.
Striker Romelu Lukaku began paying back his £75m price tag with a double on his Premier League debut for the Reds, while the rout was completed in the latter stages by substitute Anthony Martial and midfielder Paul Pogba.
The victory propelled United to the top of the table and their performance was far more attack-minded and expansive than those of recent years, providing an early hint of a challenge for top-flight honours this term.
“We finished last season winning the Europa League and qualifying for the Champions League,” said Mourinho. “We start the second season with a very good performance at home. We had many players on the pitch with a very good game. We have reasons to be optimistic.
“For me, years and years of experience and experience in the Premier League, my feet are on the ground and I am calm. Last season we were also top of the league in the first match and we finished sixth so this means nothing.
“It just means we played well and confidence levels will be high. Now our challenge is to keep this confidence level.”
Mourinho also heaped praise on Lukaku, who appeared far from shackled by his big-money summer move as he followed up his goal against Real Madrid in the Uefa Super Cup with a further two clinical strikes against the Hammers.
“He’s playing well and he’s working hard,” added the Portuguese. “He likes the team and the team likes him. Strikers can play phenomenally well, but if they don’t score goals, the pressure’s on them.”
United entered the clash having lost just one of their previous 13 opening-day Premier League fixtures at Old Trafford – against Swansea in 2014 – and never truly looked in any danger of a further setback.
The Reds took the lead on 33 minutes when Marcus Rashford seized upon a misplaced Pedro Obiang pass, surged at the Hammers defence and provided the ammunition for Lukaku to thunder an effort past Joe Hart, in off the post.
In a game of very few openings for the visitors, a presentable chance came and went in first-half stoppage-time as midfielder Edimilson Fernandes fired straight at David de Gea following skipper Mark Noble’s clever flick.
United doubled their lead seven minutes after the restart as Lukaku glanced an inswinging Henrikh Mkhitaryan free-kick beyond a static Hart – his 11th goal in 13 matches against West Ham.
Rashford’s pace and penetrative running was a recurring theme of United’s attacks and the teenager was close to his first goal of the season when his vicious strike crashed off Hart’s post shortly after the hour mark.
United settled matters late on when Mkhitaryan’s pass dissected West Ham defenders Winston Reid and Pablo Zabaleta and Martial swept past Hart, while Pogba added the coup de grace as he smashed home a low shot from 20 yards.