To say this was a mixed occasion for Tottenham Hotspur would be an understatement. There was a battling victory for the visitors to enjoy, one that moved them up to third and allowed all concerned to clear their heads following their eviction from the Champions League by Juventus last Wednesday. But a gloomy afternoon on the south coast was not without a gloomy moment, namely the injury to Harry Kane that threatens to rule Spurs’ top scorer out for the rest of the season and places questions over his involvement at the World Cup.

The prognosis does not look good given he departed the stadium with the aid of crutches and a protective boot following a collision with Asmir Begovic. The pair tangled in the 34th minute as Kane converted a cross only to be ruled offside, with his right ankle taking the brunt of the impact.

Mauricio Pochettino confirmed the 24-year-old has twisted the joint but refused to put a timescale on the striker’s absence before assessing the results of a scan on Monday. Tottenham’s manager insisted Kane was in a positive mood but the player’s reaction when he left the pitch would suggest otherwise. Having received treatment, the usually mild-mannered Kane threw a water bottle to the ground in frustration as he made his way down the tunnel.

That is understandable given the deja vu nature of the injury. Kane hurt the same ankle on two occasions last season, in September and in March, missing 14 games as a result. Tottenham have a maximum of 11 games left to play this season, with the FA Cup and Champions League qualification still to play for. The worst possible outcome is a grim one, then, with a Cup quarter-final against Swansea City next up followed by a visit to fellow top-four contenders Chelsea. And that is before England’s friendlies against the Netherlands and Italy this month are taken into account. Gareth Southgate names his squad for those games on Thursday and will surely be without the forward. The worry for him is that Kane’s absence from international duty will be even more protracted.

More will be known after his scan and until then Tottenham would be wise to focus on the positives. As Pochettino said, his players needed to show a reaction following their midweek heartbreak and they did just that, recovering from Junior Stanislas’s early goal to stretch their unbeaten domestic run to 17 matches. While the scoreline may ultimately have flattered Spurs, victory did not and it bodes well for them that this was another occasion in which Son Heung-min shone having taken Kane’s position in attack after the striker’s withdrawal.

The South Korean led the line with his usual mix of hard running and clever movement, scoring twice in the process to take his tally for the season to 17 in all competitions. Pochettino described Son’s display as fantastic and on this form there is no reason why he cannot spearhead Tottenham’s attack for however long Kane is out of action.

But Pochettino was quick to stress that this was a collective show of skill, strength and durability by this side. The visitors dominated possession and territory and during the second half in particular left Bournemouth dizzy with their slick interchange play. Érik Lamela impressed having come on for Kane, as did Christian Eriksen and Dele Alli, with the latter scoring the goal that brought Spurs level on 35 minutes.

Following a flurry of passes down Tottenham’s right Serge Aurier delivered a cross into the area that Alli sent past Begovic having darted between Simon Francis and Steve Cook. The finish was smart and sparked relief among the visitors’ ranks given that up to that point they had largely been second best.

Bournemouth had started really brightly, playing with great intensity and organisation and deservedly took the lead with Stanislas’s low drive on seven minutes. The goal was the forward’s fourth of the season and was a moment of redemption given his glaring miss three minutes earlier.

Tottenham were rattled and their afternoon appeared to be spiralling out of control when Kane limped from the fray. But then Alli scored and, following sustained pressure, Son struck twice in the space of 25 minutes, converting Alli’s cross with a miscued volley before finishing off a counterattack having run into space and calmly rounded Begovic.

That was the cue for some home supporters to leave with many no doubt cursing Mike Dean’s decision to rule out Callum Wilson’s 83rd-minute strike for a push on Davinson Sánchez. Eddie Howe described the decision as soft and he could only look on with further despair as Aurier got his first goal for Tottenham with a stoppage-time header.