Son, the current Spurs captain, is currently representing South Korea in the Asia Cup in Qatar, with Romero set to lead the team out again in Friday's FA Cup tie with holders Manchester City. Romero was captain for the 2-2 draw at Manchester United two weeks ago, with Tottenham manager Postecoglou impressed by how the Argentina centre-back Romero has dealt with the extra responsibility.
"There's definitely a void there but with all these things there's definitely opportunities," said Postecoglou. That's where Romero has really stepped up. "You just feel it around the place. He knows that Sonny's not here and he knows what Sonny does on a daily basis."
The Australian added: "Sonny gets around everyone in the building and says, 'how you going?' and Cristian's doing that now. I can see that. In training he's a lot more vocal than he was in the past. That's the beauty of it.
"There is a void because you're missing one of your leaders, but for me, on the outside, you're kind of waiting on, 'is anyone going to step up here because we're going to need someone to or do I need to interject myself into it?' But he's stepped up."
Tottenham are eight points adrift of Premier League leaders Liverpool but Postecoglou is proud of the way Spurs, beset by a string absences and still without Son and the Africa Cup of Nations exits of Pape Sarr and Yves Bissouma, have regrouped after a difficult November in what is the manager's first season at the north London club.
"There's a really good feeling amongst the group at the moment over where they're at," Postecoglou said. "They understand that because of what we've been through, 'OK, somebody's missing, man down, but somebody fills that void and we keep going until they come back'. I think it's been good for the growth of the team."
He added: "We could have flown through this first half of the year and I'm sure all the questions to me would've been, 'what happens when there's a hiccup?' and I wouldn't have been able to answer that question. "I'd bluff my way through it but I wouldn't have been able to really answer it. "But I already know, I've seen the resilience and part of that is how I've dealt with those absences."
January 26, 2024