Joel Matip says Andrew Robertson's impressive debut for Liverpool gave the impression that the left-back had played for the club for "a long, long time."
Robertson, 23, drew praise from manager Jurgen Klopp after his display in the 1-0 win over Crystal Palace at Anfield on Saturday.
It was the Scotland international's first Premier League appearance for Liverpool since his summer move from Hull City.
"He played really good," Matip told the club's official website. "His situations were really clear offensively and defensively, and you couldn't tell that it was his first game. He really played like he had played there a long, long time.
"As a defence, we try to help every teammate, it's not something special for when a new player comes in. You try to help every player, your teammates -- but he did very well without needing much help."
With Trent Alexander-Arnold rested against Palace, Joe Gomez deputised in the right-back slot.
Matip was equally impressed with the versatile youngster, who is fully fit again after recovering from a 13-month layoff last season.
"He also did really well," Matip said of the 20-year-old. "He did really good preparation, he has a lot of quality and he can play centre-back or right-back.
"He's played really both positions really well -- as he did on Saturday on the right. It was nice to see him getting minutes in the Premier League again."
Matip has played every minute of Liverpool's first three matches of the season so far -- earning two wins and a draw in all competitions, while being part of a defence that has conceded four goals in the process.
On a personal level, the centre-back says he is benefiting from an injury-free preseason campaign prior to the start of his second year at Anfield.
"It was really good for me to play and have this preparation without injuries to get a good fitness level," the former Schalke defender added.
"But like every other player, we need some more games to get to a really good fitness level, but we're on a good way. For me personally, it is good to have these games without injuries.
"Preseason is the basis for everything. It gave me a good feeling for the games I played and the games I will play in the future."