Alli came off at half-time in the opening game of the season against Everton and has since been left out of the last two games all together.
Here, the PA news agency takes a look at where it has gone wrong for Alli.
Fall from grace
After 18 months in the doldrums, it looked like Mourinho’s arrival at Spurs last November might be the catalyst for Alli to regain his very best form. After the Portuguese made a point of targeting Alli positively in the media, it paid dividends as he scored four goals in the first four games. But that form waned; he played out of position as Spurs were without a striker before Covid-19 hit and then suffered a hamstring injury in the first few weeks back after lockdown which curtailed the back end of the season.
Dressing room tantrums
In their first meeting following Mourinho’s arrival, the boss asked whether Alli was a party boy and this is another underlying issue that Pochettino often highlighted. There can be no denying that Alli enjoys the celebrity lifestyle and has featured just as heavily in the showbiz columns as the sport pages. Everyone is entitled to a holiday but Alli was regularly snapped by paparazzi in Ibiza this summer, being seen partying with James Maddison and Jack Grealish. It is interesting that the very top players, such as Harry Kane, are very rarely photographed in such circumstances.