Jose Mourinho needs time to fine-tune his Manchester United side and expects further bumps in the road over the coming months.
United laboured to a 1-0 win over Zorya in the Europa League on Thursday, failing to turn in a display to match the impressive 4-1 victory over Premier League champions Leicester City last weekend.
That result got Mourinho's men back on track following back-to-back league losses to Manchester City and Watford.
"I need time, I need the players to play, I need to see them in different circumstances," he said.
"I need to understand more about them. There is so much to learn about the players that only when you work with them for a long, long time do you know them well.
"There is always a surprise behind the door when you work with a team for three or four or five months. There is always a surprise."
Mourinho hopes to have Henrikh Mkhitaryan and Luke Shaw back at his disposal to face lowly Stoke on Sunday - the start of a daunting October schedule that features Liverpool, Fenerbahce, Chelsea and Manchester City across the Premier League, Europa League and EFL Cup.
"We need the squad, that's for sure. The Europa League is the competition that disturbs more the domestic competitions because you play on Thursdays and it is really difficult.
"Every game is massive. Watford was massive, we lost three points against Watford - not different than the three points we lost against Man City.
"Every game for me is important but, you are right, we have some big opponents in October, but that is also a motivation."