Jurgen Klopp warned Pep Guardiola and Manchester City that Liverpool know they will challenge for domestic honours this season despite their Community Shield defeat.
City claimed the first trophy of the English season with a 5-4 penalty shoot-out victory at Wembley on Sunday after the 90 minutes ended 1-1.
Raheem Sterling put City ahead against his old club during a first half in which the Premier League champions were the dominant force.
Liverpool were the better side after the break, though, with Joel Matip deservedly heading them level and Mohamed Salah and Xherdan Shaqiri each going close to scoring winning goals.
Claudio Bravo kept them at bay and proved the hero in the shoot-out when he saved from Georginio Wijnaldum, allowing Gabriel Jesus to seal victory.
Liverpool manager Klopp was encouraged by his team's efforts in the second half, though, and believes they have shown City they will push them all the way in 2019-20.
"It was a really good performance, a powerful one in the second half," he told BT Sport. "Both teams had a similar pre-season – I spoke to Kevin de Bruyne after the game and we both said we don't really know where we are yet.
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— Manchester City (@ManCity) August 4, 2019
"The least we deserved was the equaliser. One save decided it and I cannot be disappointed. The performance was much more important today than a win. We know we are still here; we can still play proper football.
"In the first half we could have adjusted better, but we had chances as well. In the second half, we changed a few things, we wanted it and, in the end, it was a little bit lucky. Congratulations to City."
Guardiola's side finished just a point ahead of Liverpool at the top of the table last term, and the City boss felt this latest encounter highlighted just how close the two teams are.
"An incredible final from both sides; no team can dominate for 90 minutes," he said. "We had real good moments, in the last 15 minutes we were exhausted, and they had chances to win the game.
"It was a good test for both teams. It's nice for the players to realise what they will face this season. At this level, the difference is nothing: one penalty, one point.
"The first title of the season is in our sights. In the second half, they played more long balls and we didn't win the second balls. We could not control it."
While Sunday's game suggests Liverpool will be City's clear challengers in the title race, Guardiola is not willing to discount the other top sides from closing the gap.
"[Manchester] United will be back, Arsenal, Tottenham, Chelsea...I don't know what will happen," he added.Published 04 Aug 2019, 23:02 IST