Marko Arnautovic played a key role in Inter Milan’s 3-1 victory over Cagliari on Saturday, helping to extend their lead at the top of Serie A to six points ahead of their crucial Champions League clash with Bayern Munich.

Substituting for the injured Marcus Thuram, with coach Simone Inzaghi eyeing the second leg of their Champions League quarter-final on Wednesday, Arnautovic gave Inter the lead in the 13th minute.

The Austria international then turned provider, delivering a perfect pass for Lautaro Martínez in the 26th minute, allowing the Argentine to chip home his 20th goal of the season in all competitions.

Despite a spirited fightback from Cagliari, who pulled a goal back in the 49th minute through Roberto Piccoli, Inter sealed the victory thanks to Yann Bisseck’s powerful header in the 55th minute.

With the win, Inter now sit six points clear of their nearest challengers, Napoli, who are due to face Empoli on Monday. However, the focus for Inzaghi’s team is now firmly on Bayern Munich, with Inter leading 2-1 from the first leg in Germany.

"We'll go into that match with a lot of confidence, even though we know we're up against one of the three or four best teams in the world," Inzaghi commented. "We need to replicate the pace, aggression, and organisation that we showed in the first leg."

Although Arnautovic has often been used as a substitute this season, his recent contributions have been crucial, with the forward netting five goals in his last 10 appearances for the club.

Inzaghi's team are hoping to replicate the historic treble of Serie A, Champions League, and Coppa Italia that they achieved under José Mourinho 15 years ago.

Treble Ambitions

Arnautovic, 35, was on loan at Inter from FC Twente during the 2010 Champions League final, when Inter triumphed over Bayern Munich to lift the coveted trophy. However, the forward admits his role back then was more that of a spectator.

"Obviously, we believe in the treble because we’re Inter, but there’s still a long way to go," Arnautovic said. "I was only a fan cheering the team on back then, but now we’re a much stronger side."

Earlier on Saturday, Venezia boosted their Serie A survival hopes with a 1-0 win over bottom-placed Monza. The victory moved Venezia to within two points of Lecce, who are just outside the relegation zone, but were defeated 2-1 by Juventus.

Juventus moved up to third place in the league standings on 59 points, following goals from Teun Koopmeiners and Kenan Yildiz in a comfortable win over Lecce in Turin.

Under new manager Igor Tudor, Juventus remain unbeaten in their last three games, after replacing Thiago Motta last month. They are now on course to secure a Champions League spot, sitting a point ahead of Atalanta, who play Bologna in Sunday’s match.

"We have to do everything we can to reach the Champions League and win every game remaining," said Juventus’ Manuel Locatelli.

Despite dominating possession and creating numerous chances, Juventus’s performance was criticised for lacking fluidity. They nearly squandered their lead when Federico Baschirotto, having scored in the previous match, headed home for Lecce in the dying minutes, but Juventus held firm for all three points.