Tottenham were leading 3-0 when Bale came on as a 72nd minute substitute for his first appearance since joining on a season-long loan from Real Madrid.
But he suffered a debut to forget as Tottenham capitulated in astonishing fashion.
The Wales star was one of the main Tottenham culprits as he missed a golden opportunity to wrap up the points before West Ham’s Manuel Lanzini snatched a stoppage-time equaliser.
Tottenham took the lead with just 45 seconds gone when Son Heung-min and Harry Kane combined to create a goal for the seventh time this season.
Kane was the catalyst, dropping deep into midfield before unfurling a majestic long pass that found Son, who cut into the West Ham area and curled his shot into the far corner.
It was Kane’s turn to get on the scoresheet in the eighth minute as he nutmegged Declan Rice and fired into the bottom corner from the edge of the area.
Tottenham’s sizzling start featured a third goal in the 16th minute, with England captain Kane heading in from Sergio Reguilon’s pin-point cross for his 10th goal of the season.
Back at Tottenham seven years after leaving for Real in a then world record deal, Bale hopes to prove he is still a world-class talent despite a long spell out of favour with Madrid boss Zinedine Zidane.
But it was West Ham who were the dominant force after Bale’s introduction to replace Steven Bergwijn.
Fabian Balbuena nodded in from Aaron Cresswell’s cross after 82 minutes and Davinson Sanchez’s headed own goal from Vladimir Coufal’s delivery three minutes later left Tottenham panicking.
Bale should have scored in stoppage-time, but he shot wide after bursting into the area and Lanzini made him pay with a brilliant 25-yard blast into the top corner.
West Ham are the first team in Premier League history to avoid defeat in a game having trailed by three or more goals as late as the 81st minute.
“The game was under control. We had Harry Kane to score the fourth when he hit the post, then Gareth Bale to kill the game. This is a game that was in the pocket and we lost two points,” Tottenham boss Jose Mourinho said.
“We should be stronger. They were lucky but maybe they deserved that luck. We were unlucky but maybe we deserved that.”
At the King Power Stadium, Villa left it until the 90th minute to seal their fourth successive victory.
Ross Barkley, on loan from Chelsea, took John McGinn’s pass and fired home from the edge of the area.
Just months after avoiding relegation on the final day of last season, Villa move up to second place.
They thrashed champions Liverpool 7-2 before the international break and now sit three points behind leaders Everton.
Villa have won their opening four games of a league season for the first time since 1930-31 and boss Dean Smith said: “It is a really good start. To come here and get the win, this is a really good team.
“There are a lot of tired legs but they are getting into the season slowly but surely. We will savour what we are doing at the moment.”
At Bramall Lane, Fulham’s Aleksandar Mitrovic endured a penalty nightmare in a 1-1 draw with Sheffield United.
Mitrovic fired over with his second half penalty after Jack Robinson handled.
Ademola Lookman put Fulham ahead in the 77th minute with a superb solo effort.
But Serbia international Mitrovic was penalised for a high foot on Robinson in the 85th minute and Billy Sharp made him pay as he drove his penalty down the middle.
Alexis Mac Allister netted his first Premier League goal in the 90th minute to give Brighton a 1-1 draw at Crystal Palace.
Van Dijk injury
Elsewhere Liverpool’s Premier League title defence was rocked yesterday when the club confirmed key defender Virgil van Dijk has suffered knee ligament damage amid reports the Dutchman could miss the rest of the season.
Van Dijk, who will require surgery, hobbled off after a shocking challenge from Everton goalkeeper Jordan Pickford in a 2-2 draw in the Merseyside derby on Saturday.
“The centre-back damaged knee ligaments following an incident involving Blues goalkeeper Jordan Pickford after six minutes at Goodison Park,” Liverpool said in a statement.
“Van Dijk was required to be substituted and further assessment on the injury has revealed an operation will be needed.
“No specific timescale is being placed upon his return to action at this stage.”
It will at the very least be months before Liverpool’s talismanic presence at the back returns from injury, leaving Jurgen Klopp with a major problem to solve to keep the Reds’ season on track.
The Netherlands captain is also at risk of missing the delayed Euro 2020 next June.
“I wish you a speedy recovery big man,” tweeted Liverpool’s top scorer Mohamed Salah.
Van Dijk has been pivotal to Liverpool’s resurgence since making a then world record 75 million pound sterling ($97 million) move for a defender from Southampton in January 2018.
The 29-year-old has started the last 94 league games to bring a defensive solidity that was lacking during Klopp’s first two years at Anfield.
Since then Liverpool won the Champions League in 2019 and ended a 30-year wait to win the Premier League earlier this year.
“You look at it now and think can Liverpool win the league without Van Dijk there?” former Liverpool defender Jamie Carragher told Sky Sports.
“Every team that has aspirations of winning the league has three or four players that if one of those players is missing, no matter how good your manager is, how big your squad is, you can’t cover for them. They are that outstanding.”
With the summer transfer window only just closed, Klopp will have to wait until January to bolster his now threadbare options at centre-back.
Joel Matip and Joe Gomez have consistently struggled with injuries themselves, while midfielder Fabinho is another option having deputised at the heart of the defence already this season.
“I think they certainly have to go into the market in January. Not just because of Van Dijk’s injury, Liverpool were weak in that area anyway,” added Carragher.
“For Jurgen Klopp and the club, right away it’s who can we get in? They have to be ready on January 1 to bring someone in.”
There are parallels with the serious knee injury that Manchester City centre-back Aymeric Laporte suffered at the start of last season.
Without the Frenchman, City’s title defence imploded paving the way for Liverpool to cruise to the league title by 18 points.
The sidelining of Van Dijk is compounded by the absence of goalkeeper Alisson Becker with a shoulder injury.
Without the Brazilian in goal, Klopp’s men have conceded nine times in their last two matches, including a historic 7-2 humiliation at Aston Villa two weeks ago.
The loss of Van Dijk’s dominant aerial presence was obvious as Everton scored twice from headers to come from behind in a contentious derby at Goodison Park.
That left the Reds three points behind their city rivals at the top of the table.
But they remain ahead of the rest of the expected title challengers with none of the Premier League’s ‘big six’ enjoying a perfect start to the season.
Van Dijk’s absence is also a bodyblow to Liverpool’s Champions League aspirations.
Their campaign begins away to Ajax on Wednesday and recent arrival Thiago Alcantara is also a major injury doubt for the trip to Amsterdam.
Klopp was not happy with another reckless Everton challenge that earned Richarlison a straight red card for taking out the Spanish international.
Thiago was able to complete the game, but has also been sent for scans to discover the extent of a knee injury.
“When I left the pitch, Thiago told me in the red card situation with Richarlison he thinks he got injured,” said Klopp.
“We will see if it’s true or not, but if he felt like this then we need to have a look.”