London: Pep Guardiola's 49th birthday celebrations went flat as Fernandinho's late own goal forced Manchester City to settle for a 2-2 draw against Crystal Palace, while Tottenham's hopes of finishing in the top four were dented by a goalless draw at Watford on Saturday.
On a busy day of top-flight action, the pitchside VAR monitor was used in the Premier League for the first time at Norwich and Arsenal were held to a 1-1 draw by Sheffield United.
It was the drama at the Etihad Stadium that took the spotlight as Fernandinho's last-gasp blunder left Guardiola in no mood to party after City's faint hopes of retaining the title suffered another hammer blow.
The champions trail Liverpool by 13 points ahead of the runaway leaders' clash with rivals Manchester United on Sunday.
Palace won the corresponding fixture at the Etihad Stadium last season and the south Londoners took a shock lead in the 39th minute.
Cenk Tosun marked his first league start since his loan move from Everton with his maiden goal for the Eagles, the Turkish striker netting a close-range strike from Martin Kelly's flick.
Sergio Aguero appeared to have turned the game on its head in the 82nd minute when the Argentine striker turned in Gabriel Jesus's cross for his 250th goal in 360 games for the club.
Aguero put City ahead in the 87th minute with a typically predatory header from Benjamin Mendy's cross.
But there was a sting in the tale for Guardiola as Fernandinho turned Wilfried Zaha's cross into his own net in the 90th minute to end second-placed City's run of three successive league wins.
NORWICH AND WOLVES WIN, EVERTON AND ASTON VILLA DRAW
Bottom of the table Norwich's vital 1-0 win over fellow strugglers Bournemouth saw the pitchside monitor finally used to decide a red card call.
Norwich took the lead when Bournemouth defender Steve Cook was sent off after flinging himself across the goal to block Teemu Pukki's shot with his hand.
Pukki fired home the resulting penalty in the 33rd minute, but the Canaries had to survive a tense finish after Ben Godfrey was sent off in the 76th minute.
Godfrey's foul on Callum Wilson was ruled a red card by referee Paul Tierney after he checked with the monitor, a move that followed advice to officials from Premier League chiefs this week to use the screen more often.
Wolves climbed to sixth after a thrilling fightback in their 3-2 win at Southampton, with Pedro Neto starting a second-half revival that saw Raul Jimenez's brace seal the points.
Everton drew 1-1 at West Ham after Dominic Calvert-Lewin cancelled out Issa Diop's opener for the hosts.
Aston Villa's Jack Grealish rescued a 1-1 draw at Brighton, who had taken the lead through Leandro Trossard.