Rosenior's reign at Stamford Bridge began with an FA Cup tie against Charlton, a relatively gentle introduction to life in the Chelsea dugout.
However, his next assignment offers a far sterner examination, with Arsenal providing top-level opposition in cup competition. The contrast between the two fixtures underlines the intensity of the challenge Rosenior now faces so early in his tenure.
Speaking at his pre-match press conference on the eve of the Arsenal encounter, Rosenior was asked whether the fixture represented the biggest game of his managerial career to date.
The Chelsea boss was keen to downplay the idea, insisting that he does not categorise matches in that way. Instead, Rosenior stressed that the next game is always the most important, regardless of opposition or occasion.
He emphasised the need for total focus from his players, making it clear that their attention must be firmly fixed on the Arsenal match alone.
Rosenior said he does not want his squad distracted by thoughts of future fixtures or longer-term narratives, believing that such thinking can undermine performance.
"People will look at it that way. But I don't see it that way. I think every session that I take, every meeting that I take, every game that we play is the most important thing. I live in the now," he said.
"It is the most important game because it's the next one. I mean that. If you start to prioritise games or think something's more important than the other, then you're not focused. I don't care if it's a pre-season game. I'm doing it at my maximum. I expect that from whichever group I work with.
"That keeps me calm because I'm happy with the process in which we work as a staff and which the players are taking on. I'm not making it any bigger than the fact it's the next game and we have to win. That's the way I see it."
Inter will be without one of their key midfielders for the Champions League clash with Arsenal after confirming Hakan Calhanoglu has suffered a calf injury that is expected to keep him sidelined for around three weeks.
Per Mertesacker will bring his long association with Arsenal's academy to a close at the end of the current season, stepping away from the role he has held since retiring as a player in 2018.
Mikel Arteta has moved to clarify Arsenal's injury situation as attention turned to Wednesday night's Carabao Cup semi-final first leg against Chelsea at Stamford Bridge, insisting there was encouragement despite a few lingering concerns.
Liam Rosenior was delighted with Chelsea's 5-1 victory over Charlton Athletic on Saturday but warned his team that it is only the beginning of a busy period.
