Ronaldo's form surprises Ferguson

Cristiano Ronaldo's Real Madrid displays have come as something of a surprise to former boss Alex Ferguson who described his form as "phenomenal".

Portugal forward Ronaldo, sold by United for a world record fee of 94 million euros ($126.57 million) in 2009, faced his old club for the first time in Wednesday's last-16 first leg tie.

"Ronaldo is a better player than when he left us because of his maturity," Ferguson said. "He's at the peak of his career now and the next three years will be the same.

"I never thought he'd ever get the amount of goals he's scored. To score the goals he has scored is phenomenal."

Ronaldo, 28, has been in scintillating form and warmed up for the United game with a hat-trick in a 4-1 destruction of Sevilla on Saturday, the 17th treble of his La Liga career. 

United are riding high with a 12-point lead at the top of the EPL while Real have all-but given up on retaining their La Liga title after some erratic efforts.