(CNN) -- Teenager Bojan Krkic scored twice as Barcelona overcame the pre-match loss of key striker Zlatan Ibrahimovic to defeat Athletic Bilbao 4-1 on Saturday night and move three points clear in Spain.
Ibrahimovic scored both goals in the Spanish champions' 2-2 draw with Arsenal in midweek, but is now ruled out of the second leg of the Champions League quarterfinal at home to the English club after picking up a calf injury in the warmup, according to the UK Press Association.
The 19-year-old Bojan stepped up for just his third league start this season in a much-changed Barca line-up, and staked his claim for a place on Tuesday with an assured performance.
It is a big week ahead for the European champions, who face second-placed Real Madrid in a key clash next Saturday which will have a massive bearing on who wins the La Liga title.
Real can return to the top on goal difference ahead of that match by winning by two scores at Racing Santander on Sunday.
Barca coach Josep Guardiola made several changes against sixth-placed Bilbao, and ended the match with eight youth-team products on the pitch after midfielder Yaya Toure went off injured.
Winger Jeffren celebrated his call into the senior team with the 26th-minute opening goal as the 22-year-old netted his first league goal of the season from Eric Abidal's cross after Lionel Messi sent the recalled France fullback free down the left.
Bojan made it 2-0 five minutes before halftime after captain Carles Puyol -- playing at right-back in the absence of the suspended Daniel Alves -- intercepted a stray pass and picked out the young forward, who has played once for Spain despite having a Serbian father.
He doubled his tally just before the hour mark with a fierce right-foot shot after Abidal again provided the ammunition, while Messi made up for an uncharacteristic first-half miss from close range when he netted from Pedro's 67th-minute cross.
It was the Argentina forward's 26th league goal of the season and his 35th overall.
Bilbao pulled a goal back through Markel Susaeta, and goalkeeper Victor Valdes twice denied Ander Iturraspe to prevent a repeat of the lapse that saw Barca blow a two-goal lead against Arsenal.
Managerless Sevilla claimed fourth place with a 3-0 victory over lowly Tenerife in Saturday's late match, with strikers Fredi Kanoute and Luis Fabiano netting in the first half before Jose Carlos curled in an 87th-minute free-kick.
Mallorca can go back ahead of Sevilla with a draw against Almeria on Sunday, while victory would lift the islanders two points clear.
Tenerife were left third from bottom and deep in relegation trouble, seven points behind closest team Santander.
Real Zaragoza moved seven points clear of the relegation zone with a 2-0 victory at home to Malaga, moving one place above their opponents.
Zaragoza followed up last weekend's 3-0 upset of third-placed Valencia as Argentine midfielder Leonardo Ponzio smashed in the opening goal just before halftime and Chile striker Humberto Suazo sealed victory with a volley from Javier Arizmendi's header with 14 minutes to play.