Arsene Wenger's team selection for Arsenal's FA Cup third-round defeat by Nottingham Forest was "arrogant", according to former Blackburn and Chelsea striker Chris Sutton.
The defending champions lost 4-2 at the City Ground to the Championship club.
Wenger made nine changes from their Premier League draw with Chelsea on Wednesday.
"The emphasis has to be on playing a strong side in the cup games," Sutton told BBC Radio 5 live.
"You can blood couple of youngsters, but make sure you have big hitters on the bench. It is arrogance beyond belief from Arsene Wenger."
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It was the first time Wenger has lost a third-round match in his 21-year Arsenal tenure.
The Frenchman, who is serving a three-match touchline ban, said after the match that he made the changes to his team knowing that they have a Carabao Cup semi-final on Wednesday against Chelsea.
"We have many players on the edge [of fitness]," said Wenger.
"When you don't win, the selection is always questioned. I believe we had an experienced team - eight or nine internationals. It would be easy to think that was the problem."
Last year's losing finalists Chelsea also made nine changes for their first FA Cup game of the season on Saturday, and came away with a 0-0 draw and replay against Norwich.
Fellow Premier League sides Bournemouth and Leicester made eight changes each and drew with League One sides Wigan and Fleetwood respectively.
Tottenham made eight changes but were able to bring on Son Heung-min and Dele Alli as substitutes in their 3-0 win over League One AFC Wimbledon.
Arsenal, however, had an inexperienced bench, with Calum Chambers the only player to have made a Premier League start for the club.
"It is super arrogant to think you will breeze past Forest," added Sutton.
"If you knew the game was going to be difficult, why would you not pick your strongest team? He has prioritised the League Cup over the FA Cup.
"Wenger has taken Nottingham Forest too lightly. He has to carry the can for that. Arsenal are regressing under Wenger."