The 26-year-old, who over the last few years has struggled to rediscover his best form, provided a glimpse of his potential during Friday's 3-0 victory.
Alli not only got on the scoresheet but also received a standing ovation from the Besiktas fans following a much-improved display.
After the match, the England international said (as quoted by Fanatik): "I wanted to show people what I can do, this is my source of motivation.
"When I came here, people had expectations. I couldn't show what I could do, but this match is what I focused on. It's not mine but the team's performance that is important. I will do my best in every match."
The England international received a hero's welcome from the club's passionate fans when he first arrived on loan from Everton in the summer.
However, that relationship quickly soured following a string of poor performances.
Alli was booed off the field in late December when he was substituted after 28 minutes of Besiktas' cup clash with second-tier Sanliurfaspor. The midfielder made two brief substitute appearances in the following six games.
Friday's win over Alanyaspor marked Alli's first appearance in the starting line-up since December's cup debacle.
Manager Senol Gunes will be hoping for more of the same as Besiktas continue to pile pressure on Fenerbahce and Galatasaray in the title race. The Black Eagles are currently third and are seven points adrift of the top.
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