Title-chasing Manchester City stumbled at home as they were held to draw by relegation-threatened Nottingham Forest to fall seven points adrift of Premier League leaders Arsenal.
With the top two kicking off at the same time on Wednesday evening, the Gunners edged past Brighton while Elliot Anderson's brilliantly-curled finish 13 minutes from time stole a crucial point for Forest at Etihad Stadium.
The visitors had been sitting back and allowed City to dominate possession without really threatening in the opening stages, though Semenyo sent a warning sign by arrowing an effort into the side-netting.
The hosts made their pressure count just after the half hour mark when Rayan Cherki dinked a cross into the box and January signing Semenyo caressed a delightful volley for his seventh goal since joining City.
Forest had chances on the break either side of the goal but Morgan Gibbs-White's tame effort was gathered low down by Gianluigi Donnarumma and the Italy international also batted away a swerving low drive from Igor Jesus.
But against the run of play, Forest drew level on 56 minutes courtesy of skipper Gibbs-White's stunning finish, instinctively backheeling a finish past Donnarumma following Igor Jesus' knock down.
City looked to respond and Erling Haaland's strike deflected off Murillo and looped on to the roof of the net, with midfielder Rodri heading in from the resulting corner to restore their advantage.
But with time running out, England international Anderson curled in from 25 yards out for a precious point which keeps Vitor Pereira's side outside the relegation zone on goal difference.
Line-ups
Man City XI: Ruben Dias, Bernardo Silva, Donnarumma, Rodri, Haaland, Foden, Guehi, Antoine Semenyo, Rayan Aït-Nouri, Matheus Nunes, Cherki
Subs: Ake, Stones, Omar Marmoush, Reijnders, Nico González, James Trafford, Doku, Savinho, Abdukodir Khusanov
Nottingham Forest XI: Sels, Aina, Sangare, Elliot Anderson, Milenkovic, Gibbs-White, Dominguez, Neco Williams, Igor Jesus, Jair Cunha, Murillo
Subs: Gunn, Taiwo Awoniyi, Hudson-Odoi, Ryan Yates, Dan Ndoye, Luca Netz, Morato, McAtee, Omari Hutchinson
Yohabi1
72
If not for Semanyo, Manchester City would be outside top 4 by now.
Ksm_city
37
WE DONT DESERVE TO WIN THE LEAGUE!!!
Nganyewo
35
Dream Big, work hard , The only way forward is by moving forward. Congratulations to Arsenal
Lazbdopruy
34
Wow, Arsenal just gave me reason to sleep well tonight! Tnx lads! Gunners for life ..
Abcdefootball
30
After signing Semanyo, Haaland is nowhere to be found in City or in Forest.
EmeraldJ
30
Can we now agree to give the EPL to Arsenal? They've shown consistency and seriousness more than any other club this season
Carybary
23
The GIF is already here, my pleasure: https://www.matchgif.com/v2/live/matchGifs?match_id=54154616&language=en
Shanihajji
22
arsenal surely gonna win this season by God's grace INshaAllah
VinUnited
21
The JOY landed at Emirate 😄😄😄👏
Barca_Mancity_12_com
20
city were robbed🤦
Wuaabinoy
19
Arsenal in the wild our language Arsenal ku chalo
KrithikMatthew
16
worst game day by day. too slow like a turtle. boring
layackmpu
15
thank u Arteta once more!!!🤙🤙🤙🤙🤙but guys, Haincape is a beast,get that deal done please Mr Berta!! let's not focus on city and never let that gap reduce,we go game by game, all praise and glory to almighty God!
womeinort
13
Forest draws Man City, the pain remains at the Etihad and the joy goes to the Emirate stadium
Simdeiloy
10
EPL is the worst football management on earth, imagine foul on Haaland two times that suppose to result to penalty referee removed his eyes VAR pretended and goes blind,even if you want to give league to Arsenal you organize it well not messing up football.