In truth, Chelsea’s 5-1 victory flattered them on Saturday, but substitutes Liam Delap, Pedro Neto, Enzo Fernandez and Estevao Willian proved too much for a tired Charlton side to handle.
Rosenior is the first Chelsea manager to win their opening match since Antonio Conte in August 2016, enjoying the largest margin of victory since Luiz Felipe Scolari in August 2008.
“I have to say I was delighted with the starting XI,” Rosenior said. “I was delighted with the first three. I felt that Ale (Garnacho) continued in his one-on-ones.
“Marc Guiu was magnificent, he deserved his goal. Jamie (Gittens) looked like he was going after the defenders. He looked like he could create in a lot of moments. So a lot of real positives and a good start.”
The most impressive performer was defender Jorrel Hato, who scored the first goal and played the role played by Marc Cucurella last season.
Hato, 19, made reverse runs into attacking midfield positions while Chelsea were on the front foot, found himself in dangerous areas and ultimately capitalized.
The £37m summer signing from Ajax has already struggled at Stamford Bridge, but since Maresca left the club he has produced arguably his best three performances, playing significant minutes against Manchester City and Fulham in recent league matches.
“I saw him play at Fulham,” Rosenior said. “I was so impressed with him then. He took that form to another level today. Not just in terms of goalscoring, I felt his defensive qualities were excellent.”
There were concerns when Rosenior explained that Cole Palmer, Reece James and Malo Gusto had been ruled out due to knocks sustained in the defeat at Fulham last Wednesday – particularly with tougher tests ahead.
Arsenal are next in the Carabao Cup semi-final on Wednesday, while Chelsea host Brentford at Stamford Bridge on Saturday.
“He’s going to be judged on his performances against decent teams in the Champions League, against Arsenal, Manchester City, Liverpool, Aston Villa – those are the teams he’ll be judged against, so we’ll have to see,” former Chelsea winger Pat Nevin told 5 Live.
“He’s had a great month with a lot of games where he can see a lot of players. Four home league games, two away league games – and one of them is Wolves, who haven’t had a great season so far.
“There is no easy route, but this is as friendly as possible. He will have learned which of his players are fringe players. There are quite a few he will be happy with.”
But it wasn’t all happiness: Chelsea fans continued to protest against the ownership throughout the match and even chanted “attack, attack, attack” as their team waited until halftime to break through.
The atmosphere among the supporters remains feverish, in a context of distrust towards the owners. This is a potential pitfall that Rosenior needs to be wary of given that, as a rookie to Todd Boehly and Clearlake Capital’s other club, Strasburg, he could easily be called a yes-man.
Asked about the chants, Rosenior said: “All I’m going to focus on right now is working as hard as I can to help this team reach the potential – the unlimited potential – that it has. And if you focus and concentrate on your work, I hope people see that we’re on to a good thing.”
