Kylian Mbappé scored for the seventh match running as pulled provisionally level on points with La Liga leaders Barcelona after a 3-0 win at 10-man on Saturday.
Reigning champions Barça visit , third, on Sunday, aiming to move back clear of the chasing pack. José Mourinho's Madrid largely dominated at Mestalla stadium as they secured an eighth win in a row across all competitions.
Federico Valverde and Arda Guler's first-half goals put Madrid in the driving seat and Mbappé added a third in the second half, bursting on to a dangerous pass by Guler to dart past Stole Dimitrievski and squeeze home his 13th league goal of the campaign.
secured a 2-1 victory over in the Bundesliga on Saturday but the form of goalkeeper Manuel Neuer will again be in the spotlight after another error almost produced an equaliser for the home side in the first half.
Neuer became Bayern's oldest player at 40 years, 225 days, overtaking Bernd Dreher, but was forced off with a recurrence of a foot injury that had kept him out of recent matches, replaced before half-time by Jonas Urbig.
Neuer was left flailing at a cross that resulted in Mainz's Lee Jae-sung putting the ball in the back of the net with Bayern leading 1-0, though the effort was ruled out for offside.
Neuer's mistake against Augsburg last month, which resulted in the fastest-ever Bundesliga goal after eight seconds by Robin Fellhauer, was the latest in a growing number for the keeper once regarded among the best in the world.
According to Sofascore using Opta data, that error was his fifth that led to a goal in his previous 17 Bundesliga games, or one every 3.4 matches. In 248 appearances before that, he made just 10 such errors, or one every 24.8 games.
Neuer has played twice since that Augsburg fixture, which ended 2-2, missing four games with the foot injury. He returned for this week's 2-0 Champions League win at Atlético Madrid.
The Ballon d'Or winner Harry Kane could not find the net against Mainz but did provide two assists for Joshua Kimmich and 18-year-old Lennart Karl as Bayern extended their unbeaten away run in the league to 31 games.
They maintained their lead at the top of the Bundesliga from Borussia Dortmund with both clubs on 21 points from nine games. Bayern have a superior goal difference.
were given a scare by promoted but won 2-1, thanks to two goals from Felix Nmecha.
Third-placed , who are three points behind the leaders, won 5-2 at home to , while Jonathan Burkardt scored a 93rd-minute equaliser for as they drew 2-2 at in a battle between two mid-table sides.
missed the chance to climb into the top four when they lost 1-0 at , where an early goal from Maximilian Mittelstädt settled the contest.
Illia Zabarnyi scored the only goal of the game as a weakened claimed an unspectacular 1-0 win over in Ligue 1 to make it 11 consecutive victories in all competitions.
The Ukraine defender Zabarnyi headed in Senny Mayulu's cross to break the deadlock in the 39th minute at the Parc des Princes, and that proved sufficient to beat their newly promoted opponents who lie in the bottom three.
PSG's neighbours won 1-0 away to thanks to a second-half goal by the in-form striker Lassine Sinayoko.
Mali forward Sinayoko, a summer signing from Auxerre, opportunistically turned in an assist by Pablo Pagis, who was called up to the France squad for the first time by Zinedine Zidane on Friday. Sinayoko, 26, is the top scorer in Ligue 1 with nine goals in 10 games. Liam Rosenior's Paris FC are second, three points behind PSG.
moved up to second Serie A with a 3-0 win over at the Stadio Olimpico.
Sassuolo held out until the 27th minute when the Roma defender Mario Hermoso drove forward towards the area. His attempted pass to Donyell Malen was intercepted but he gathered the loose ball, took a touch to make space and fired into the roof of the net.
Three minutes later, Malen's shot took a touch off a Sassuolo defender before Sebastian Walukiewicz turned the ball into his own net. Sassuolo's goalkeeper Arijanet Muric kept his side in the game with saves from Leonardo Balerdi and Matías Soulé before the break but Rodrigo Mora's 58th-minute goal put the game out of reach.