Gary Neville says that he realised Liverpool would be Premier League title contenders when they signed Virgil van Dijk and Alisson Becker.
Jurgen Klopp's side opened up a 25-point lead at the top of the table before the season was suspended until April 30 at the earliest due to the coronavirus pandemic.
The Reds finished second last term, finishing just a point behind champions Manchester City, having been battling for Champions League qualification in previous campaigns.
And Manchester United legend Neville says he began to fear his former club's arch-rivals when they began to spend big money in the transfer market.
Liverpool acquired Van Dijk for £75m in January 2018, before capturing Alisson for £66.8m a few months later.
"It did always feel like [Liverpool] were toying at it in the transfer market, you wouldn't quite go for the best players,” Neville told Sky Sports.
"There was a feeling you either couldn't go for the best players because financially you didn't have the money or you couldn't attract the players to come to Liverpool because Arsenal were better, we [Manchester United] were better.
"You weren't at that time attractive to come to as a club because you hadn't won the league for a number of years.
"It always felt like you were toying with it in the transfer market. If the market was at £13m, £15m, Liverpool were at £8m. If the market was at £25m, you were sort of at £16m. You were never quite up there.
"I think that's what's shocked me in the last few years about what Jurgen Klopp's done. Because up until the point where he went for Alisson and Van Dijk, Liverpool still weren't going to the levels of the other clubs.
"The other clubs were at £60m-70m, whereas Liverpool were at sort of £25m-30m, maybe getting to £35m.
"All of a sudden, you talk about the last piece of the jigsaw, and then all of a sudden Van Dijk happens and then Alisson happens and you think 'Oh'. They were the last pieces of the jigsaw in essence."
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