Former Arsenal defender Nigel Winterburn believes Arsene Wenger must mount a title challenge after signing a two-year deal.
Boss Wenger has penned a contract extension at the Emirates until 2019 to end months of speculation over his future.
The Gunners won the FA Cup after beating Chelsea 2-1 on Saturday and Wenger's new contract was ratified by the club's board this week.
But they finished fifth, 18 points behind the Blues in the Premier League, last season to miss out on the Champions League for the first time under Wenger.
And Winterburn, who won the Premier League in 1998 with Arsenal under Wenger, insists it is time for the Frenchman to end Arsenal's 13-year title drought.
"They've made the decision, so it's now time to put in a serious title challenge," he told Sky Sports News. "There's probably 20-25 per cent that would like to have seen a change.
"He's in charge and we're now expecting some significant signings and I would love to see the team progress. He's come through a difficult period. They went backwards after going into the new stadium - now's the time to be serious for the title.
"I know a lot of people have been saying typical Arsenal that they make this announcement at the end of the season. It's my understanding there was no decision until after the FA Cup final.
"The club statement was positive and it will be interesting to see what happens in the transfer window."
Former Gunners goalkeeper Bob Wilson warned Arsenal and Wenger they may struggle to attract top signings having failed to reach the Champions League.
"How are you going to get Antoine Greizmann to sign? Without the Champions League, the only way is if you can compete salary-wise to attract the players,' he told BBC Sport.
"Chelsea bought the best player available last season in N'Golo Kante and Arsenal went for him too but came nowhere near the salary that Chelsea pay.
"So the board has to be realistic and say, 'Are we going to compete at this level?'"
Television presenter and Arsenal fan Piers Morgan vented his frustration at the news of Wenger's new deal.
Wenger, who has called repeatedly for a change in manager, said on Twitter: "Wenger wins. I lose. Arsenal will keep failing in any competition that matters. Sad, mad, inexplicable day.
"As promised, I will now never tweet about Wenger again. It's over. #Afc."
Arsenal midfielder Santi Cazorla, who is currently out with an ankle injury and expected to miss the start of next season, said Wenger had worked "miracles" at the club.
He told Spanish radio station Cadena Ser: "He is key to this club. He hadn't told us anything (regarding a new deal)m but we are all delighted. The coach has done great things for the club, not just now but in the past. The club values his career. He has done miracles."
But John Hartson, who played for Wenger at Arsenal in the Frenchman's first few months in north London, questioned whether the manager had a squad capable to consistently challenge for major honours.
"I can't understand how this group of players can win the big trophies. Yes, they won the FA Cup and that's great, but unless he's got a big transfer fund and Wenger is willing to pay, then Arsenal aren't capable of winning the Premier League," the ex-striker told Sky Sports News.
"They won't win it with this group. They need a central defender and a forward. They are deluded if they think they can win the Premier League with this group of players.
"Top players like working with other top players and you know the other clubs will strengthen. Unless Arsene goes in for the top, top players in the world, they can't do it. If they make three or four top players they have every chance of competing for the Premier League.
"They have the contract situation with (Alexis) Sanchez and (Mesut) Ozil - and he'll have to go for the big players. The other clubs will spend big. Buying big will be one way of appeasing the fans who aren't happy."