The Brazilian winger also set up a goal for La Liga's top scorer Jude Bellingham, who now has 11 to his name this season in the Spanish top flight. Madrid climbed a point clear of high-flying Girona, who host Athletic Bilbao on Monday looking to reclaim top spot.
Carlo Ancelotti's side also rose four points clear of fourth-placed rivals Barcelona, following their 1-1 draw at Rayo Vallecano on Saturday, and third-placed Atletico Madrid.
Madrid were dealt severe blows over the past fortnight with Vinicius Junior and Eduardo Camavinga suffering long-term injuries, joining Thibaut Courtois, Eder Militao and Aurelien Tchouameni on the sidelines.
Ancelotti started Toni Kroos in defensive midfield and brought veteran playmaker Luka Modric into the team for only his fifth start in La Liga. Bellingham also returned after missing two league games with a shoulder injury.
Madrid dominated the opening stages and took the lead after 14 minutes when Rodrygo dribbled across the penalty area and curled a sumptuous strike into the top right corner.
The Brazilian struggled for goals at the start of the season but Ancelotti kept faith in him and with Vincius sidelined, he will be crucial for Madrid in the coming weeks. Rodrygo's goals mean he has scored in three consecutive games for the first time since arriving at the club in 2019.
November 26, 2023
Cadiz had their chances in an open first half too, with Chris Ramos heading over before Rodrygo's opener and Andriy Lunin tipping Roger Marti's fierce effort to safety.
Madrid should have doubled their lead early in the second half after Rodrygo dribbled around Cadiz goalkeeper Conan Ledesma, but Joselu left it to him to finish, and he in turn left it for the veteran striker, with the ball running out of play.
However, Rodrygo had his second soon enough, another fine strike after dribbling into the box from 30 yards out. After Maxi Gomez missed a fine chance for the hosts, the inspired Rodrygo set up the third for Bellingham and the England international drilled a tidy low finish across goal with his left foot.
With the job done, Ancelotti withdrew both goalscorers and handed young forward Gonzalo Garcia his debut. Madrid host Napoli on Wednesday in the Champions League having already qualified from the group but looking to seal top spot.
Earlier Sunday, Marcelino Garcia Toral enjoyed a 3-0 win on his return to La Liga management with Villarreal, with Jose Luis Morales' hat-trick sinking Osasuna 3-1. Real Sociedad earned a 2-1 win at Sevilla, who had Sergio Ramos and Jesus Navas sent off.
November 26, 2023