Rafael Benitez says Jurgen Klopp's Liverpool will have to win something before they can be regarded as a great team.
Benitez, 57, spent six years as Liverpool manager between 2004-2010, winning an FA Cup and a Champions League trophy.
The Spaniard returns to Anfield on Saturday as Newcastle manager hoping to derail Klopp's side, who have lost just once in their last 19 Premier League fixtures.
Klopp's side have been revered for their attacking performances this season but Benitez maintains they need to land silverware before they can be considered equals to previous successful Liverpool teams, including the side he managed.
Speaking ahead of Saturday's game, he said: "We won four trophies, we played three finals, we reached the semi-final of the Europa League, so the time that we were there with the results that we had, we did well and the people remember that.
"They don't talk about this week when we won 5-0 against Aston Villa. They remember maybe when we beat Barcelona and Real Madrid, but they don't remember the games. They remember the stat or they remember the trophies.
"When you are doing well, that is important. The way you do things is really important and after, you have to win. But I think that they have the potential to do it."
Benitez is mostly remembered for masterminding Liverpool's comeback in the 2005 Champions League final against AC Milan in Istanbul, but says his best team on Merseyside were the team which finished runners-up in the Premier League in 2008/09.
Everybody knows it was a team that needed to improve to win the Premier League and we were improving later on", he continued.
"The best team we had at this time was the team that finished second in the league with 86 points. We had [Fernando] Torres, [Steven] Gerrard, [Javier] Mascherano, Lucas Leiva - everyone was doing well. We were building something for years.
"In the first year, we played the final of the Carling Cup and we won the Champions League, but this team was not ready yet.
"People say we were lucky in the final but no, we did really well to get there, the team was working very hard tactically. But in terms of quality, we had more of that two or three years after."