Romero returned to the Tottenham line-up for Sunday's 4-3 loss to Chelsea after he'd missed the last four matches with a toe injury.
However, the Argentinian was forced off in the 15th minute when, according to Tottenham boss Ange Postecoglou, he 'felt something in his quad' in a 'hugely disappointing' blow.
Two minutes after Romero went off, Chelsea winger Jadon Sancho scored to make it 2-1.
Enzo Maresca's side would score three more goals before Tottenham skipper Heung-min Son's consolation in second-half stoppage time.
With Tottenham now winless in their last four across all competitions and with one victory from their last seven, the heat is cranked up on Postecoglou.
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However, Romero believes the pressure should be intensified on those working above the Australian, especially when considering the levels of investment from the likes of Chelsea, Liverpool and Manchester City.
When asked on the Universo Premier podcast if Tottenham had fallen behind their top six rivals in terms of investment and squad strength to compete for titles, Romero said: "The truth is, I would say no comment, but... Manchester City competes every year, you see how Liverpool strengthens its squad, Chelsea strengthens their squad, doesn't do well, strengthens again, and now they're seeing results.
"Those are the things to imitate. You have to realise that something is going wrong, hopefully, they realise it.
"The last few years, it's always the same: first, the players, then the coaching staff changes, and it's always the same people responsible.
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"Hopefully, they realise who the true responsible ones are, and we move forward because it's a beautiful club that, with the structure it has, could easily be competing for the title every year."
Since Postecoglou arrived in July 2023, Tottenham have spent £348million on transfers.
Only three players signed by Postecoglou - Micky van de Ven, Dominic Solanke and Brennan Johnson - featured in Tottenham's starting line-up against Chelsea.
It is worth noting all five players who came off the bench for Tottenham - Radu Dragusin, James Maddison, Archie Gray, Lucas Bergvall and Timo Werner - were also signed under Postecoglou.
Despite the expenditure with Postecoglou at the helm, it has yet to translate into material success.
However, the same could be said for just about every manager who has sat in the dugout since Levy became a member of the Tottenham board in December 2000.
In that time, Tottenham have won a solitary trophy: the League Cup in 2008.
It took until the 2009/10 season for Tottenham to qualify for the Champions League.
Tottenham have also failed to finish higher than 4th since the 2018/19 campaign, which proved to be Mauricio Pochettino's final full season in charge.
Given the stature of the club and their membership in the so-called 'Big Six', more is expected of Tottenham.
It appears Postecoglou will be given the opportunity to turn things around, as talkSPORT understands the Australian is not under immediate threat of being sacked.
The loss to Chelsea dropped the north London outfit into the bottom half of the table, which has sparked supporters' fury.
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But Levy is understood to be more content to stick rather than twist and is aware Postecoglou has been hit with injuries to several key players.
Postecoglou and Tottenham have the chance to break the winless streak when they travel to Ibrox for a Europa League clash against Rangers on Thursday.