LONDON, Mar 14 (SW) - Chelsea boss Jose Mourinho has insisted that Frank Lampard will remain at Chelsea if Bayern Munich captain Michael Ballack joins the Blues in the summer. He envisions the two attacking midfielders forming the core of a strengthened Chelsea side.

"This will be a dream couple in Europe and the big advantage is that you have two world-class players all of the time," Mourinho said to the London paper The Sun.

"You can compare him [Ballack] with Frank. He is highly concentrated when it comes to scoring and will set up a lot as well. They're the two best players in the world in their category.

"If there is only one, you are dependable on your team-mates. But now there are two players with the same level who can assist each other at all times."

While Ballack has not signed with the Blues, his move to Stamford Bridge is all but secured, with both Ballack and Chelsea expressing interest. "There is strong interest from both sides," his agent Michael Becker said. "Nothing is signed but there are ongoing talks."