Los Angeles (AFP) - Saul "Canelo" Alvarez cruised to a unanimous decision over Julio Chavez Jr. in a 12-round mismatch on Saturday then announced in the ring that his next fight would be against Gennady Golovkin.

After crushing Chavez, the World Boxing Organisation light middleweight champ said he is set to face middleweight champ Golovkin on September 16.

"Golovkin, you are next, my friend. Where are you? It's on," the Mexican said before bringing Golovkin into the T-Mobile Arena ring with him.

Golovkin did not have to travel far to make the announcement as he watched Alvarez's fight from ringside in Las Vegas.

"Congratulations," he told Alvarez. "I feel excited to be part of this big drama show."

The 26-year-old Alvarez used Chavez for target practice, landing jabs, hooks and combinations at will as he won every round of the 75 kg fight on all three judges' scorecards.

He landed 228 punches to just 71 for Chavez and an incredible 31 per cent of his jabs connected as he had his way with former champion Chavez.

Alvarez improved to 49-1-1, with his only loss coming against Floyd Mayweather in 2013.

There was no title on the line Saturday as Alvarez moved up in weight to fight the much bigger Chavez.