'Bloody hell, we've been kind to them’ - Man United legend issues warning to Liverpool’s £240m signings

The pair represent a massive investment for the club, with Isak's £125 million transfer setting a new Premier League record, narrowly eclipsing Wirtz's £116 million fee. 

However, both players struggled to make a significant impact in their debut seasons as Liverpool surrendered their league title to Arsenal and finished a disappointing fifth.

Their underwhelming form continued into the new campaign's opening fixture, a 2-2 draw away at Newcastle United. 

Speaking on his podcast, Neville did not hold back in his assessment, arguing that the star forwards are "too nice" and lack the necessary tenacity.

"The big thing for Liverpool is they've got a quarter-of-a-billion-pound front-two, Isak and Wirtz, and bloody hell we've been kind to them," Neville stated. 

"They are going to have to start playing soon or else... they're going to get a lot of criticism. They're going to have to start delivering."

The former defender added, "For a start, they're too nice, and if you're going to be nice, you better be incredible at football. 

“I don't see a tenacity in Wirtz in particular—Isak maybe a bit more—but in Wirtz, I just see a nice player moving around the pitch, not really ever looking like he's busting a gut to do anything."

Neville singled out Wirtz for his languid style, expressing a desire to "put a rocket up him" to spark a change. 

"You have players that are more graceful that just flow around the pitch—like [Mesut] Ozil and [Kai] Havertz—but I want to put a rocket up him," he continued. 

"I don't see him combining with Isak. So for me... he drifts too much. I just feel like Wirtz has got to think about being involved in the build-up less; he's got to think about being a second striker rather than a third midfield player."

Wirtz and Isak will have their next opportunity to respond to the criticism when Liverpool face Nottingham Forest in Saturday's early kick-off.