Hansi Flick believes that Wojciech Szczesny can become a big player for Barcelona this season after his Champions League heroics against Benfica on Wednesday. 

Szczesny made eight saves for Barcelona in their 1-0 win over Benfica in the first leg of their last 16 tie, a huge result after Pau Cubarsi's 22nd-minute red card. 

Benfica had 26 shots against Barcelona, their most on record (since 2003-04) in a Champions League match without scoring, which was all down to Szczesny's display. 

The 34-year-old has become a mainstay in Flick's team since coming out of retirement last October following Marc-Andre ter Stegen's season-ending injury. 

Szczesny has kept eight clean sheets in his 14 appearances across all competitions this season, conceding just 13 times, with Flick happy with his performances thus far. 

"He is fantastic. The other players were defending 10 against 11, and he helped us a lot. That is his job. We cannot hide it," Flick told reporters on Friday. 

"He does his job very well, and that is why he is now the number one. 

"When you watch players in training, you get a feeling. I discuss it with my staff. I see how the players work and what level they can reach.

"It was clear to everyone that Szczesny could reach this level. We all knew it. I make the decisions, but I talk with my coaching staff."

Barcelona now turn their attention to LaLiga action, with 11th-placed Osasuna the visitors to the Camp Nou this weekend. 

Flick's side are one point clear at the summit of the standings, but the Barcelona boss is wary of Osasuna, who inflicted the Blaugrana's first loss of the season in September.

Osasuna were 4-2 victors in the reverse fixture, having lost each of their previous five games against them. Barcelona, however, have never lost both matches in the same campaign against this weekend's opponents in LaLiga.

"It was different, we played away. Tomorrow, we have to field the best possible team. I think our performance level is different now. I am optimistic about tomorrow's match," Flick said.

Barcelona have won each of their last six LaLiga matches, keeping four clean sheets in four of them, having won just one of their previous eight in the competition (D3 L4).

They are also the first team to score 71 or more goals in their first 26 games of a LaLiga campaign since they did so themselves in 2016-17 (76 goals).

"It is always good to be positive and to maintain a positive image at all times. If you approach things from a negative perspective, trying to avoid mistakes, I don’t think that’s good. We can defend well as a team," Flick concluded. 

"It will be a tough game - I always say the same. They played very well there, pressed us well, also in one-on-one situations. It was difficult for us to get out of their press. We will try to be prepared."