Tottenham boss Mauricio Pochettino says the club need a "big summer" if they are to challenge for Champions League qualification next season.
Their 2-2 draw with Southampton on Saturday further harms their chances of a top-four finish.
Pochettino says there will need to be investment if they are to challenge the Premier League's top sides.
"We need to prepare for a big summer, build a strong team and fight for the top four," Pochettino told BBC Sport.
"Our dream for our supporters and this club is that they deserve to fight for the top four and be in the Champions League."
Last week Pochettino said being in the Europa League had hindered his side's domestic campaign.
And while he concedes that another season in the competition would be far from ideal, the club will still take the Europa League seriously if they are in it.
"After my experiences of last year it's tough to play in the Europa League," he said. "I prefer to play in the Champions League but if you reach the Europa League it's good for the club.
"If we reach the Europa League next season, we must try and do better and fight for the top four and to try and win the Europa League, but it is not my dream."
European football is still far from guaranteed for Tottenham with Southampton remaining a point behind them in seventh place, with four games to play.
Liverpool, in fifth place, are also in contention for a top-six finish with Brendan Rodgers' side having played one game fewer than Spurs and Saints.
Pochettino was returning to St Mary's for the first time since his acrimonious departure last summer and he said it had been an "emotional" occasion for him.
The Argentine said he still loved Southampton while thanking his own fans for their support.
Ben Davies was carried off during the game and Pochettino revealed the defender had suffered a shoulder injury, but added he was "OK now" and would be "assessed later in the week".
Saints manager Ronald Koeman said he was disappointed after his side twice let the lead slip, but proud of his side's continuing challenge for sixth place.
"If you can't win the game, don't lose the game," Koeman told BBC Sport.
"Maybe we had the best chances but this is the way I like to play football."