With international duty injuries leaving Xavi with a selection headache, the former Barca player chose to give teenager Ansu Fati his second start of the season and his first in the league.
However, it was the hosts that started brightly and a goal seemed inevitable until Barcelona went ahead in the 20th minute when Fati stole the ball up the pitch and passed to the Polish striker who cut inside and curled a shot past Predrag Rajković.
With his goal, Lewandowski became the first player to score in six consecutive La Liga weeks since Ruud van Nistelrooy in the 2006-07 season.
With Lewandowski doing his job, it was Marc-Andre ter Stegen’s turn to keep Barcelona in front against Mallorca. The German had to keep out Jaume Costa’s goalbound effort in the 35th minute to ensure his side maintained the lead.
Things did not improve much after the break and he was called into action again and again as Mallorca looked for an equaliser. The 30-year-old, however, kept out efforts by Antonio Sanchez and Lee Kang-In to secure all three points for his side.
Xavi’s side now once again leads the La Liga table with 19 points one ahead of Real Madrid who has a game in hand.
Meanwhile, Atletico Madrid defeated a struggling Sevilla 2-0 thanks to goals from Marcos Lollrente and Alvaro Morata to get its league campaign back on track.