Gonzalo Higuain struck his 21st Serie A brace to go joint-top in the scoring charts as Juventus opened up a seven-point lead with a comfortable 2-0 win at 10-man Cagliari on Sunday.

Higuain's 17th and 18th goals of the league season means the Argentina striker is tied with Roma front man Edin Dzeko, who missed a penalty then made amends with Roma's second in a 2-0 win at Crotone.

Juventus, claiming their 20th win in 24 games, remain top of Serie A with a seven-point lead on Roma.

Third-placed Napoli are nine points behind the Turin giants, days ahead of a crucial Champions League trip to Real Madrid.

Juventus are not in action in Europe until they visit Porto on February 22 and Massimiliano Allegri's men have capitalised to further underline their bid for a record sixth consecutive title.

Despite Juve's numerical advantage after Nicolo Barella saw red for a second caution on 67 minutes, Higuain says it wasn't as easy as it looked.

"We did well, but it was a difficult match because we just couldn't get into our stride at the start," Higuain told Premium Sport.

“Once we broke the deadlock, it started going a lot better, and even more so after their expulsion."