Celtic boss Ronny Deila has said that he is expecting a tough test when his side travels to Tannadice Park on Sunday to face Dundee United.
The Hoops thrashed the Terrors 6-1 when they last met in the league, but the Norwegian coach believes that their opposition has dramatically improved since.
"I like the way they play football. They defend hard with a very good team spirit and are very direct, very good in counter-attacks and also score a lot of goals from set pieces," Sky Sports News quotes Deila as saying.
"They are a very good team and have brought on a lot of young players.
"They also sold players for good money and still keep the team up. That's the sign of a good culture and a good club."
Celtic have won their last eight matches on the bounce, a run that has helped them climb to the top of the Scottish Premiership.