Pedro Rodriguez filled in for Barcelona's missing star forwards by netting a hat trick in 10 minutes before setting up Cesc Fabregas twice as the visitors erased a two-goal deficit in a wild 5-2 win at Getafe on Sunday.
Barcelona's entertaining victory ensured the defending Spanish champions retained their share of the league lead with Atletico Madrid two rounds ahead of their meeting in the capital.
Real Madrid needed a late goal by substitute Jese Rodriguez to earn a 3-2 victory at Valencia to stay in third place and five points behind its title rivals.
With Barcelona's strike-duo Lionel Messi and Neymar unavailable, Getafe surged forward from the start and stunned the visitors' shaky defence with two goals in 15 minutes.
But Pedro led the comeback by scoring in the 34th, 41st and 43rd minutes to swing the match in Barcelona's favour before halftime.
Pedro crossed for Fabregas to score his first goal in the 68th before Pedro provoked a penalty in the 72nd that Fabregas converted to secure the result.
In his fifth season with Barcelona's first team, the 26-year-old Pedro has settled for a role of reserve player with the occasional start. Despite his limited playing time, Pedro's second treble of the season made him Barcelona's leading scorer in the league with 10 goals, tied for fourth best overall.
"I'm happy, confident and taking advantage of the opportunities my coach gives me," Pedro said. "The game was difficult. We didn't play well in the first few minutes, but we switched it on and pulled out the win."
Also, Athletic Bilbao beat Rayo Vallecano 2-1 at San Mames to strengthen its hold on fourth place.
Espanyol routed Valladolid 4-2 for its first win at home in four rounds, and Celta Vigo salvaged a 1-1 draw at home with Osasuna after Manuel "Lolo" Ortiz scored an own goal to cancel out teammate Emiliano Armenteros' opener.
Barcelona was without the injured Messi, Xavi Hernandez, and Victor Valdes, while Neymar was suspended.
But it was the first-choice defensive line that struggled early on, despite having Dani Alves back from a monthlong injury.
The Brazilian back looked rusty, Javier Mascherano was often out of position, and Gerard Pique conceded two unnecessary corner kicks— the second of which led to Getafe's second goal.
After Pique had missed a chance for Barcelona, left back Sergio Escudero worked a one-two with Angel Lafita to speed by Dani Alves and give Getafe the 10th-minute opener.
Centerback Lisandro Lopez was then completely unmarked to head in Pedro Leon's corner, leaving Barcelona coach Gerardo Martino to scratch his head and pace the touchline.
But Fabregas and Andres Iniesta took control of the ball and suddenly it was Getafe's defence that sprang leaks, especially down the left flank occupied by Pedro.
"The best part of the win was the team's attitude during the comeback," Pedro said.
Pedro pulled the first one back when Fabregas threaded a ball through for the forward to fire a looping strike that goalkeeper Miguel Moya touched but couldn't stop from going into the net.
Iniesta was next to find Pedro, who cut back to his right foot and unleashed an untouchable shot just inside the far post.
Pedro was helped by Getafe on his third goal. A defender flubbed in his attempt to clear Jordi Alba's low cross after Fabregas had played him wide, and instead laid the ball off for Pedro to pound it past Moya.
Pedro turned playmaker after halftime.
Fabregas volleyed in Pedro's lobbed pass at the far post, and the former Arsenal captain scored from the spot after Pedro was brought down by Borja Fernandez in the area.
Barcelona will face Getafe twice more in January in the Copa del Rey's round of 16.
At Mestalla Stadium, Angel Di Maria blasted Madrid in front in the 28th when he controlled Marcelo's lobbed pass, dribbled between two defenders and drilled in a left-footed strike.
Juan Bernat set up the equalizer for Valencia when he picked out Pablo Piatti with a cross to head in the 34th-minute equalizer.
Cristiano Ronaldo put Madrid back in front with a header in the 40th for his 18th league goal of the season. But Valencia toughened its defence after halftime and defender Jeremy Mathieu fended off Sergio Ramos to head in a corner in the 62nd for the 2-2.
Jese went on in the 73rd and nine minutes later he capped Madrid's buildup after Luka Modric spotted him on the right side by rifling a low shot between goalie Vicente Guaita and his near post.
"This result is important," Madrid coach Carlo Ancelotti said. "We are excited for 2014, even though Barca and Atletico are leading and are favourites [to win the title]."
The league takes a two-week break for the winter holidays from Monday.