LONDON -- Manchester United made a double transfer coup in time for the start of the premier league season on Saturday with the signing of Brazil midfielder Kleberson and Portuguese teenage striker Cristiano Ronaldo.

The English champions invested in their future strike power by signing 18-year-old Ronaldo from Sporting Lisbon for 12.24 million pounds ($19.60 million) on Tuesday.

United also replaced Juan Sebastian Veron, the Argentine they transferred to Chelsea last week, with 24-year-old Kleberson, a World Cup winner with Brazil last year, from Atletico Paranaense for 5.93 million pounds ($9.49 million), Reuters reported.

Both players signed five-year contracts and join Cameroon midfielder Eric Djemba Djemba, French striker David Bellion and U.S. goal keeper Tim Howard as United's close-season recruits.

"We're delighted Kleberson is joining us because we've been chasing him for quite a few months," United manager Alex Ferguson said.

"He played in the World Cup final for Brazil, and his then coach Phil (Luiz Felipe) Scolari said he was first choice every time in the team. The new Brazilian coach (Carlos Alberto) Parreira says the same.

"He is a young, athletic midfield player who can play in a number of positions. One of the reasons we sold Seba Veron was because we knew we were getting Kleberson -- that shows how highly we regard his talent," Ferguson said.

"To be the first Brazilian to sign for United is special," Kleberson said. "This is the biggest opportunity of my life. I had offers from other clubs but they weren't Manchester United. What I promise the fans is to give my all on the pitch from the outset."