Arsenal manager Arsene Wenger will need to spend in the summer to enhance the club's chances of competing in the latter stages of the Champions League, according to Nigel Winterburn.
The Gunners were beaten 2-0 by Barcelona at the Emirates Stadium on Tuesday in the first-leg of their Champions League last-16 tie, leaving Wenger's side with a huge uphill task in their bid to secure a quarter-final berth.
Arsenal have not progressed past the last-16 stage of Europe's elite competition since 2010 and Winterburn feels his former club must invest in the playing squad to stand any chance of progressing further in the competition in the future.
"You could sense from Arsene Wenger's interview that he felt Arsenal had wasted an opportunity last night," the former Arsenal defender told Sky Sports News HQ.
"It's easy to analyse after a game and say 'if we'd had a 20-goal-a-season striker, would he have taken those chances', [but] we just don't know that.
"They've come up short again in the last-16 so that says to Wenger he's going to have to look at that at the end of the season.
"If they are going to move on from where they are and really be considered as one of the favourites for the competition, they are going to have to improve the squad again and I think Wenger knows that.
"But at this moment in time, what he needs is the support of all the supporters because they have a huge 12 games coming up in the league and they are still in the FA Cup. Then we can really analyse where Arsenal came up short in the Champions League."
Arsenal will now turn their attentions back to the Premier League title race and their clash with Manchester United at Old Trafford on Sunday, live on Sky Sports 1 HD from 1pm.
Despite giving his backing to Wenger, Winterburn fully expects Arsenal's performance to be scrutinised if they fail to pick up a victory over an under-achieving United team.
"Louis van Gaal is under pressure with speculation that he will be leaving at the end of the season," Winterburn added.
"From Arsenal's point of view, people are going to be scrutinising to see where they sit in the title race and if Arsenal don't win a game, there will be a lot of analysis.
"Arsenal are in a new period, from last season to next season and the end of Wener's contract. There is money at the club and they expect Arsenal to challenge for the title."