The 21-year-old midfielder is making headlines for the wrong reasons after being booked for simulation in Spurs' 2-2 draw at Liverpool on Sunday - a booking he did not protest in the slightest.
It was the second time that the Tottenham ace has received a yellow card for diving this season, and his third caution for the offence overall.
No other Premier League player has been punished for simulation more than Alli and Collymore claims that the youngster must "pull the finger out" and start making headlines for the right reasons again.
"Alli is basically acting like a spoilt brat and building up quite a rap sheet — the latest entry being the dive against Liverpool on Sunday," he wrote in The Mirror.
"This sort of thing has been going on with him for quite a while now, and he needs to pull his finger out otherwise he will have a major problem.
"He must shape up, help Tottenham win something and then move to one of the big boys of the football world — which he could easily do."
Alli is indeed a huge talent but his form has dropped quite a bit this season, having only managed five goals in 25 Premier League games so far and it looks like it could be his worst-ever individual campaign in a Tottenham shirt.
Still, he is only 21 and certainly has time on his side with regard to ironing out those creases.