Real Madrid captain Sergio Ramos headed a 90th-minute equaliser as Los Blancos came from one goal behind to draw 1-1 with Barcelona in Saturday afternoon's El Clasico at Camp Nou.

Luis Suarez's header early in the second period looked to be securing all the points for the home side, but Ramos levelled in the final minute as the Madrid giants remained six points clear at the top of La Liga.

There were no real surprises in the Barcelona XI that took to the field, with fit-again Andres Iniesta named on the bench, leaving Andre Gomes in midfield alongside Sergio Busquets and Ivan Rakitic as Luis Enrique took no chances.

As for Real Madrid, Raphael Varane was preferred to Pepe at the heart of the defence, while Mateo Kovacic and Isco were both given midfield roles behind a front three of Cristiano Ronaldo, Karim Benzema and Lucas Vazquez.

The away side had a shout for a penalty inside the opening three minutes when Vazquez went down under a clumsy challenge from Javier Mascherano, but the referee was not interested during what was a very lively start to proceedings in Barcelona.

It was Barcelona that had the first real chance of the match in the 10th minute when Neymar drove past Dani Carvajal before picking out Sergi Roberto with a smart cross, but Ramos was on hand to block as Real Madrid survived their first dangerous moment.

Real Madrid's first attempt on target arrived in the 16th minute when Ronaldo angled a header towards goal, but it was always comfortable for Marc-Andre ter Stegen. Down the other end, Neymar found Luis Suarez with a smart cross, only for Ramos to make another important block as the game started to open up.

Isco and Neymar were both booked in the opening 30 minutes of action, but it could have been a lot more as both teams continued to fly into challenges. Clear chances, however, remained extremely few and far between at Camp Nou.

Ronaldo brought a smart save from Ter Stegen in the 37th minute after breaking into the Barcelona box and those two players again came head-to-head less than 60 seconds later as the Barcelona goalkeeper was forced to keep out a poked effort from the Portugal captain, who outshone Lionel Messi in the first period.

Varane also came close for Real Madrid in the latter stages of the first half after finding himself unmarked from a corner inside the Barcelona box, but the French centre-back headed straight at Ter Stegen as the visitors ended the opening 45 minutes firmly on the front foot against their Clasico rivals.

Real Madrid also had the first shooting chance of the second period in the 52nd minute as Zinedine Zidane's side continued to look the more likely, but Ronaldo fired into the stands after being released into a wide position.

Less than one minute later, Barcelona took the lead as Luis Suarez, who had struggled to make his mark in the first period, rose inside the Real Madrid box to head a Neymar free kick into the back of the net and send the home supporters into jubilation, although there did seem to be a hint of offside about the goal.

If the cheer for the opening goal was loud, that was eclipsed in the 60th minute when Iniesta made his comeback from a knee injury, which immediately brought a more secure look to a Barcelona midfield that was overrun for long stages of the first period.

Zidane's first use of his bench came in the 66th minute as Casemiro replaced Isco, but Barcelona should have scored a second moments later - Neymar driving into the box and somehow firing over the crossbar, before Iniesta hit the side-netting in what was a strong period for the Catalan giants.

Marco Asensio was thrown on as Real Madrid looked for a strong finish, but it was Barcelona that continued to look the more likely and Messi missed a gilt-edged chance eight minutes from time as he somehow fired wide of the far post after breaking into the away side's box.

Mariano Diaz was Real Madrid's last substitution late on as the Dominican looked to add to his hat-trick in the Copa del Rey during the week, but it was the skipper Ramos that came up with the goods as he headed a Modric free kick past Ter Stegen to ensure that Los Blancos continued their unbeaten start to the season.

Next up for Barcelona is their final Champions League group match at home to Borussia Monchengladbach on Tuesday night, before returning to La Liga action with a trip to Osasuna on Saturday afternoon.

Real Madrid, meanwhile, will welcome Borussia Dortmund in the Champions League on Wednesday night, before continuing their league campaign at home to Deportivo La Coruna on Saturday night.