Kai Havertz fired Chelsea through to the Champions League last-16 stage as his second-half strike secured a hard-fought 2-1 victory against Salzburg.

Mateo Kovacic's first-half effort gave the Blues the lead, but the hosts hit back swiftly in the second half, Junior Adamu capping off a fine counter-attack.

Goalkeeper Philipp Kohn was called upon in both halves to keep the visitors at bay but could do nothing with Havertz's winning effort, as the Germany international drilled in to end Salzburg's 40-game unbeaten home run.

Victory means Chelsea's spot in the knockout stages is confirmed, while Graham Potter's side could still be confirmed as group winners if Dinamo Zagreb fail to beat Milan in the Croatian capital.

Opportunities were few and far between until Chelsea took the lead after 22 minutes, Kovacic drilling a shot into the top-left corner after the ball fell kindly to him just outside the area.

Three minutes after the break, Salzburg equalized on the counter as Maximilian Wober's superb cross-field pass found Adamu and the 21-year-old jabbed a first-time finish past Kepa Arrizabalaga.

Adamu then had a major impact at the other end, superbly clearing Jorginho's header off the line to prevent the visitors swiftly retaking the lead.

There was no denying Havertz three minutes after the hour mark, however, as he collected Christian Pulisic's pass just outside the box and fired home a fine finish in off the left post to leave Kohn helpless.

The hosts had chances for an equalizer, notably with Thiago Silva needing to be alert to clear Strahinja Pavlovic's header off the line as the Chelsea defense stood firm.