The former Aston Villa winger completed his £20 million move yesterday.
Kuyt told liverpoolfc.tv: "I think he will be a great signing. He did very well for Aston Villa last season and I believe he was their best player.
"I already knew of him when he was playing for Middlesbrough. He's a very good winger and a player in the team who could be very helpful for us.
"When I arrived at Liverpool Football Club almost five or six years ago, we had two very good players who could play in the same position. I've just got a feeling we're getting back there. At a club like Liverpool, you have to have every position doubled up, and it looks like more or less in every position we have at least two players.
"There is more rivalry, there is more competition but that is what makes you better and gets the best out of you. I'm ready to have this competition with the players but we also have to stick together and make it one good team to challenge with the best."