Cristiano Ronaldo ended a three-game goal drought as holders Real Madrid won 2-0 at Schalke 04 to take a big step towards the Champions League quarter-finals and equal the competition record with a 10th straight win.

The world player of the year headed in after 26 minutes for his 73rd Champions League goal with Real's first chance and he set up Marcelo to make it seven wins for the Spanish side in seven Champions League games this season and 10 in a row.

Real's victory was nowhere near as emphatic as last season's 6-1 romp at Schalke at the same stage of the competition but it was a much-needed confidence boost for Carlo Ancelotti's team after a lacklustre start to the year in Spain.

Looking to become the first team to retain the Champions League title, Real, eliminated from the King's Cup this month and crushed 4-0 by Atletico Madrid in La Liga, host Schalke in the second leg on March 10.

Elsewhere, Porto hit back with a late Danilo penalty to hold FC Basel 1-1 in a game that featured a goal controversially disallowed after a long delay and consultation.

Derlis Gonzalez gave the Swiss champions an 11th minute lead but Danilo replied in the 79th minute, calmly scoring following a handball by veteran Argentine defender Walter Samuel.

Source: Reuters