Bayern Munich midfielder Renato Sanches had a goal and an assist in his return to Benfica in a 2-0 victory on Wednesday.
Sanches, a Benfica youth product who joined Bayern in 2016 but hardly played before being loaned out to Swansea City last season, earned a rare start due to the injury of Thiago Alcantara.
He made the most of his chance as Bayern cruised despite a string of injury absences that also included Corentin Tolisso, Kingsley Coman and Rafinha.
Sanches emerged as a teenaged sensation following Portugal's Euro 2016 victory, but Bayern fans had seen little of his abilities until Wednesday.
Bayern, who have won all their competitive matches so far this season, opened the scoring after 10 minutes when Sanches sent Franck Ribery down the wing. Ribery charged through and Robert Lewandowski completed the move with a fine turn.
Benfica, who have not scored more than once in their last 10 Champions League home matches, had to wait almost half an hour for their own first chance, a header that was deflected wide.
Sanches then picked up where he had left off before the break and, with a 40-metre sprint, launched a quick Bayern move that he finished off with a tap-in as he received a standing ovation.