That is according to former Gunners midfielder Stewart Robson, who says the former Paris Saint-Germain boss oversaw what was ultimately a disappointing campaign in his first season in charge.
Emery replaced the outgoing Arsene Wenger last summer but was unable to break their Champions League hoodoo of recent seasons.
The Gunners missed out on a place in next season’s competition by losing in the Europa League final and finishing fifth in the Premier League.
Struggles defensively and in midfield left the team short and Emery is on the hunt for summer reinforcements.
But a transfer kitty of just £40m means the club are struggling to bring in much quality for next season.
So far only young Brazilian striker Gabriel Martinelli has been signed in the transfer market.
Emery has entered the second year of his three-year contract at the club but bosses have a break clause that they can trigger if they so wish after two seasons.
And Robson reckons a poor start to the upcoming campaign could mean things end badly for Emery.
“It was a disappointing campaign”
“It was a disappointing campaign,” Robson told ESPN FC. “They could have got in the top four last year, but they fell away at the end.
“They could have won the Europa League but they did’t and fell away against Chelsea.
“It needed restructuring, they lost a lot of players like [Aaron] Ramsey, Petr Cech has gone which I think is probably a good thing now.
“I think there’s a whole list of players that have left Arsenal. They’ve brought one player in, Martinelli from Brazil.
“They need a lot of new players, they need a new philosophy. I think Unai Emery may be running out of time.
“He hasn’t got the bloke they brought in to do the transfers [Sven Mislintat], he’s left, so he obviously didn’t get on with Unai Emery.
“Unai Emery needs a good start to the season. If he doesn’t get it, he is going to be under massive pressure.
“If he doesn’t buy players and doesn’t seem to get the team in the right shape for the start of the season, Arsenal are going to struggle.”