Tottenham manager Mauricio Pochettino said his side "need to improve a lot" despite edging to victory over Cardiff to equal their best start to a Premier League season.

Eric Dier scored the only goal of the game in the eighth minute, tapping in a loose ball from inside the six-yard box from a corner.

Cardiff, who had to play most of the second half with 10 men after Joe Ralls was sent off in the 58th minute, remain without a win this season and fall to bottom of the table.

Spurs have 18 points after eight games - their joint-best total - and are third in the table, one point behind leaders Manchester City, who are ahead of Liverpool on goal difference.

Their next match is against West Ham on 20 October after the international break, their first of seven games in 22 days.

"We are one point off the top of the Premier League but we need to improve a lot," Pochettino said.

"Now we have two weeks before the next game - but it is a very tough schedule when we return."

Spurs produced a lethargic performance against a battling Cardiff, who could have equalised midway through the first half but Toby Alderweireld cleared Josh Murphy's effort off the line.

The hosts lost their way after going in front but improved at the end of the first half, with Lucas Moura missing two good chances and Son Heung-min also shooting over.

Immediately after half-time, Cardiff captain Sean Morrison brilliantly blocked Moura's shot on the line after Harry Kane's initial header had been saved.

Ralls was then sent off for a cynical challenge on Moura but minutes later Morrison had a header turned onto the post by Spurs goalkeeper Hugo Lloris.

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Spurs just do enough

It seems remarkable that Spurs were described as a club in "mini-crisis" last month after losing three consecutive games - because now they have achieved their joint-best start to a season.

That tricky period at the start of September included league defeats by Liverpool and Watford as well as a Champions League defeat to Inter Milan.

The three points against Cardiff were secured despite a ponderous display which came three days after Spurs were beaten in an enthralling encounter in the Champions League by Barcelona.

Pochettino made just three changes to his team, although he had little other option with key first-team players Dele Alli, Christian Eriksen and Jan Vertonghen all injured.

Spurs' build-up play was slow and the movement up front was not as evident as in previous games.

When they did create chances they were wasteful. Moura headed off target in the first half and put a shot from seven yards wide, although in the second half he could have done little more with his shot that was brilliantly blocked by Morrison.

Captain Harry Kane was quiet. His two shots on target were a shot from distance in the first half and a header at the start of the second.

Cardiff show fight but lack quality

The defeat is Cardiff's fifth in a row in the league and leaves them in 20th place after Huddersfield grabbed a point at Burnley.

The results look bleak for the Welsh side but there were positives in the performance that will please Neil Warnock.

Some might have expected Cardiff to fold after going behind early on, but instead they were the better side for 20 minutes after Dier's goal.

They would have scored in that spell but for Alderweireld's goalline clearance, which was made even more impressive by the fact Junior Hoilett was closing in to tap home Murphy's initial shot.

Cardiff also defended valiantly when Spurs did attack, with Morrison and fellow centre-back Sol Bamba repeatedly using their body to block shots.

Manager Neil Warnock looked furious with Spurs' players after Ralls was sent off, and afterwards suggested they had influenced referee Mike Dean's decision.

Ralls' tackle was not dangerous - nor was he the last man in defence - but as he made no attempt to player the ball Dean chose to dismiss the midfielder.

"I don't think Mike Dean would have given a red card by himself," Warnock said. "I think there were too many voices around him that changed his mind.

"Players and officials all want to get in on the act and make headlines, but it's little old Cardiff isn't it?"

Cardiff again responded well to this setback, hitting the post through Morrison - but in the end the tiredness of playing with 10 men meant they were not able to push for an equaliser late on.

Man of the match - Sean Morrison (Cardiff)

'Little old Cardiff' - manager quotes

Tottenham manager Mauricio Pochettino said: "After Barcelona on Wednesday, the most important thing was to win. We created a lot of chances but we didn't kill the game. I'm happy to finish with 18 points going into the international break. We only conceded a few chances and we finished the game on top.

Cardiff manager Neil Warnock said: "When I look at Danny Rose's challenge on Bruno Manga, that is worse [than Ralls' challenge] in terms of violent conduct.

"But we kept our discipline and we kept going, so there were lots of positives. To see Spurs keep it in the corner against 10 men shows how well we did. I'm disappointed on the goal - it's a nothing cross - but you thought that would open the floodgates and I'm delighted with how we stuck at it."

Kane's struggles against Cardiff - the best stats

• Tottenham are unbeaten in their past 38 Premier League home games against promoted sides (W35 D3).
• Cardiff are winless in their first eight games to a league season for the third time, and first since 1989-90 in the old Division Three.
• The Bluebirds have lost five consecutive Premier League games, their worst run ever in the competition.
• Tottenham have scored at least once in each of their past 19 Premier League home games, the longest current run in the competition.
• Cardiff had six shots on target in this match, the most they have managed in a Premier League game this season.
• Cardiff remain the only side Tottenham striker Harry Kane has faced but not scored against in the Premier League. The England forward had six shots on Saturday, more than any other player in the match.
• Spurs' Dier scored his first Premier League goal in 546 days, since netting against Watford at White Hart Lane in April 2017.
• Ralls' red card was only Cardiff's second in the Premier League, with Juan Cala against Sunderland in April 2014 the other.

What's next?

Tottenham's next match comes at West Ham on 20 October following the international break. Cardiff host Fulham on the same day.