Bayern Munich’s smooth passage into the Champions League knockout stage hit a speed bump on Wednesday after it emerged that versatile Austrian international David Alaba could be out for the rest of the year.

All appeared well for Pep Guardiola’s fast and flexible team when they beat Roma 2-0 at the Allianz Arena to maintain their perfect record after four games and advance to the Round of 16 by winning their group with two games to spare, the fastest ever by a German team.

However, the influential Alaba limped off with a knee ligament problem in the 81st minute after another inspired display, an injury that could see Austria’s sportsman of the year miss the remainder of the year.

“David is a complete football player and he can play in any position,” Guardiola told reporters.

Alaba started in defence but switched positions throughout the match, tormenting the Italians with darting runs as he set Franck Ribery up for the opener and had several attempts on goal himself, including a long-range free-kick that just missed.

The 22-year-old Austrian is usually deployed as a full-back, combining down the left flank with Ribery but is equally effective in Bayern’s midfield, as was the case on Wednesday.

Alaba is maturing into exactly the type of player Guardiola needs as he strives to perfect an already dominant Bayern team that has yet to taste defeat in any of their 16 games in all competitions this season.

“We will be missing a super type of player, who plays outstanding football,” Guardiola said.

Further medical checks to determine the extent of his ligament injury were to be conducted in Munich yesterday but his Spanish coach is already resigned to losing the player for a number of months.

“It is a shame, a real pity because he could be out for two or three months. I hope he will be back after Christmas because he is extremely important for us because of his flexibility,” Guardiola said.

Bayern are already missing the injured midfield trio of Bastian Schweinsteiger, Thiago Alcantara and Javi Martinez.