Real Madrid's Cristiano Ronaldo (R) celebrates scoring a penalty kick with teammates Gareth Bale (L) and Javier Hernandez "Chicharito" (C) during their Champions League Group B soccer match against Ludogorets at Santiago Bernabeu stadium in Madrid December 9, 2014. [Photo/Agencies]

MADRID - Real Madrid made it six wins out of six in Champions League Group B and set a Spanish record for consecutive victories when a Cristiano Ronaldo penalty set them on the way to a 4-0 success at home to 10-man Ludogorets on Tuesday.

Already through to the last 16 as group winners, holders Real romped to a 19th straight victory in all competitions, surpassing the record of 18 they jointly held with Barcelona.

Carlo Ancelotti's men came close to scoring several times before the Bulgarian champions were reduced to 10 men after 19 minutes when midfielder Marcelinho handled at a corner to keep out a Raphael Varane header and was shown a straight red card.

Ronaldo slotted his spot kick down the middle with a cheeky chip for his 72nd Champions League goal, overtaking former Real striker Raul (71) and moving into second overall behind Barcelona forward Lionel Messi (74).

Gareth Bale headed in off the underside of the crossbar at a corner to make it 2-0 in the 38th minute, Alvaro Arbeloa added an 80th-minute third and substitute Alvaro Medran struck the fourth for the dominant home side two minutes from time.

"In theory it was an easy game because they were left with 10 (men) very early on," Real's Spain playmaker Isco said in an interview with Spanish television.

"A night like tonight is to be celebrated," he added. "They are 19 straight wins by a team that still wants to improve."

PROLIFIC RONALDO

Fired by Ronaldo's prolific scoring form, Real have won all their games since a 2-1 La Liga defeat at home to city rivals Atletico Madrid in September.

They are the first club to win all six Champions League group games twice, having achieved the feat under Jose Mourinho in 2011-12.

Only four other teams have managed it -- AC Milan in 1992-93, Paris St Germain in 1994-95, Spartak Moscow in 1995-96 and Barcelona in 2002-03.

Ludogorets had a chance of securing third place and claiming a berth in the Europa League ahead of 2005 European champions Liverpool if they had avoided defeat at the Bernabeu.

Instead, Liverpool go into the continent's second-tier club competition after drawing 1-1 at home to second-placed FC Basel, who join Real in Monday's draw for the Champions League last 16.