Harry Kane has damaged lateral ligaments in his right ankle and is not expected back in training until next month.
Kane has endured several absences with ankle problems over the last two seasons, first damaging ligaments against Sunderland in September 2016
While Tottenham have largely stayed on track without him, there is no denying their performance has been affected.
Kane has won the Premier League golden boot for the last two seasons and shares the lead once more this time around, so it is no surprise that the biggest impact is to their goals-per-game record - dropping from an average of 2.3 per game in all competitions with Kane to 1.7 without him.
Focusing on league matches alone, Spurs' points-per-game tally is also affected - dropping from 2.2 per game to a round two. While that may seem a small difference, it represents a point every five games or 7.6 over the course of a season.
Kane has appeared in all but one of their 30 games to date this season - without him, we could expect them to be six points worse off which would drop them out of the Champions League places into fifth.
They made light of his departure against Bournemouth on Sunday as Son Heung-min stepped into a central role to score twice in a 4-1 win.
That took the Korean eighth in this season's top-flight scoring chart with 12 goals and he has 30 in 91 in his Premier League career, or 0.3 per game.
He cannot compare to Kane's 0.7 goals per game, though it should be noted that Son often operates from a deeper or wider role in support of Kane and has far fewer shooting opportunities.
Kane's absence is, as manager Mauricio Pochettino noted after the Bournemouth game, a "concern" for Spurs - but they have shown before that they can cope without him and will remain confident of a top-four finish.