Millwall came back from the dead to snatch a thriller against 10-man Leeds United while Championship leaders Wolves were shocked at home on Saturday.
Aston Villa continued their march into automatic promotion contention with a comfortable win over Barnsley that moved them within a point of Cardiff City, who settled for a scoreless draw with Sheffield Wednesday.
At the other end, Sunderland struck a major blow in the battle against the drop by edging out Hull City.
KARANKA'S GIANT-KILLING FIRST WIN
Beaten at home in his first match in charge, Aitor Karanka toasted the perfect response from Nottingham Forest as they upset runaway leaders Wolves at Molineux.
Quickfire goals from Kieran Dowell and Ben Osborn late in the first half proved enough for the visitors to claim their 11th victory of the campaign.
Karanka's former club Middlesbrough also eased to an encouraging away win at Queens Park Rangers, with Daniel Ayala and Adama Traore netting either side of George Friend's long-range thunderbolt.
Tony Pulis' men remain a point of shy of fellow playoff hopefuls Fulham after they romped to a comprehensive 6-0 thrashing of bottom-placed Burton Albion.
MILLWALL'S LATE REVIVAL CLAIMS TOPSY-TURVY THRILLER
In a rollercoaster clash at Elland Road, Millwall saw a two-goal advantage wiped out by 10-man Leeds before a pair of late strikes rescued an incredible 4-3 away win.
Liam Cooper's dismissal for a late tackle sparked a skirmish in the tunnel and compounded a horror first half for the Whites as they trailed to goals from Aiden O'Brien and Lee Gregory.
But the hosts rallied back through Kemar Roofe and a Pierre-Michel Lasogga brace to lead by the 62nd minute, only to be cruelly denied a result by last-gasp strikes from Tom Elliott and Jed Wallace.
The heartbreaking defeat leaves Leeds three points adrift of sixth following Sheffield United's valuable 2-1 success at Norwich City, where James Wilson and Clayton Donaldson were on target for the Blades.
COLEMAN'S FAITH IN YOUTH REWARDED
Sunderland's young brigade continue to have a major say in the Black Cats' battle against relegation after teenager Joel Osoro scored the only goal in a 1-0 victory over fellow strugglers Hull City.
The 18-year-old notched what proved to be the winner just 20 minutes into his first league start at the Stadium of Light, moving Chris Coleman's side level on points with the Tigers, who remain out the drop zone on goal difference only.
Birmingham City and Bolton Wanderers both remain in trouble following 1-1 draws with Preston North End and Ipswich Town respectively, while Reading are edging closer to danger after their winless run in the league stretched to eight with a 1-0 loss at home to Brentford.
Lasse Vibe grabbed the winner in the 74th minute to keep the Bees well in playoff contention.