BARCELONA -- Ousmane Dembele was unable to make an impact as he came off the bench to return from a month on the sidelines in Barcelona's goalless draw with Getafe on Sunday.

Barca failed to register a shot on target in the first half at Camp Nou, with Ernesto Valverde bringing Dembele and Andres Iniesta on just after the hour in search of a breakthrough.

Philippe Coutinho, Luis Suarez and Yerry Mina all came close to scoring but Barca had to settle for a second consecutive league draw, with their lead over Atletico Madrid now down to seven points

Dembele was introduced on the right wing but endured a frustrating 30 minutes on his return from a hamstring injury.

The France international, who missed four months earlier in the season with a ruptured tendon, struggled to beat his man and was wasteful with the ball in just his eighth appearance for the club since his €105 million summer move from Borussia Dortmund.

"Dembele came on at a moment when we thought he could help us out by running at players in one-on-one situations," Valverde said at his postmatch news conference.

Ousmane Dembele cut a frustrated figure over a disappointing 30 minutes. Getty Images

"Maybe you could tell that he's not played a lot of football recently, though, because it didn't go quite as well as he would have liked against a strong opponent.

"He had to try and use his strengths, which is when he's up against players and driving at them. He didn't have much luck with that today, but it's better that he tried those things than to not try anything."

Valverde said he was impressed with how his makeshift defence had coped with the sporadic Getafe threat.

With Samuel Umtiti suspended, Thomas Vermaelen injured and a half-fit Gerard Pique not risked, the Barca coach handed Mina a full debut in the middle of the back four, with left-back Lucas Digne partnering him.

"The positive news was the performance of the two centre-backs, Yerry and Lucas, who both did well," the coach added. "Lucas was out of position and it was Yerry's first start, so it wasn't the usual defence but we got through the game without too many scares.

"At the beginning they had to adapt quickly because Getafe were pressing high. They got better as the game went on and we were able to play out from the back as usual. We are happy with them because it was a difficult role."

Valverde said the draw should serve as a warning to his side that nothing had been sewn up yet, with Atletico beating Malaga on Saturday to cut the gap at the top.

"It's a result which shows everyone that there's still a long way to go in the league," he added. "We're still going to have to sweat and push hard to win it."