Injuries to Wayne Rooney, Chris Smalling and Phil Jones has seen Louis van Gaal blood a number of academy graduates
Indeed defender Tim Fosu-Mensah and midfielder James Weir were the latest to be handed their debuts in United's 3-2 victory over Arsenal on Sunday
Watford head to Old Trafford to face Van Gaal's patched-up side in the Barclays Premier League on Wednesday night
But Flores does not believe United's star-studded treatment room makes them any easier a proposition
"I don't like to say to the players, 'come on boys, now Manchester United are a little bit weak because they have injuries, because they are younger, because they don't have experience', no, it is the opposite," said Flores.
"I try to send other messages to the players, saying take care and don't relax. Yes, they are younger, but they have a lot of passion, and they want to show everyone they are ready to play in the Premier League
"So, of course we will play a very tough match, and this is the idea we try to translate to the players. Maybe this is not the best XI they have in the squad, but they are playing really, really well."
Source: PA