Pep Guardiola believes Watford could rouse themselves to make life tough for Manchester City on Sunday.
City need at least a point in their final game of the season at Vicarage Road to earn another shot at the Champions League.
But, given Watford's recent troubles - with five successive defeats preceding a decision to part company with manager Walter Mazzarri this week - City will be expected to claim the win that will secure third place in the Premier League.
Guardiola, however, is taking nothing for granted and has warned that the 16th-placed Hornets are capable of finishing the campaign with a flourish.
"I believe a lot in the football players," Guardiola said. "Football players are so professional. They want to win, they want to make a good performance.
"It's the last game, so in the end Watford have made a good season (because) from weeks ago they were safe.
"When you analyse player by player, they always have very good players. You have to be careful."
City moved back into third with victory in their rearranged game against West Brom in midweek.
Yet their job is not done because fifth-placed Arsenal are still just three points behind.
It might seem unlikely, but City could still miss out on the top four altogether if they lose, Liverpool overcome Middlesbrough and Arsenal improve their goal difference by at least five in beating Everton.
Guardiola is widely expected to revamp his squad in the summer but, such is his determination to win this weekend, he has so far refused to discuss that in depth.
Speaking at his pre-match press conference, he said: "On Sunday, we have another final, and we have to focus on that. If you want to talk about the past or the future - next time, next season."
City go into the game in good heart after sweeping West Brom aside with a convincing 3-1 win on Tuesday.
Guardiola said: "We played better in the last game against West Bromwich Albion. They were a defensively strong team but we were able to create a lot of chances. We conceded one goal and one more chance, no more than that.
"That is the way we have to try to do better next season."