Nottingham Forest stretched their unbeaten Sky Bet Championship run to eight games as manager Steve Cooper celebrated a 4-1 victory over former club Swansea

All the goals came in an action-packed second half as Philip Zinckernagel and Lewis Grabban put Forest into a two-goal lead before Joel Piroe gave Swansea hope.

But the outstanding Brennan Johnson profited from Ben Hamer’s goalkeeping howler and substitute Cafu struck deep in stoppage time to wrap up the points.

Cooper had twice taken Swansea to the Championship play-offs in his two years at the club, with his final game being a Wembley defeat to Brentford in May.

The Welshman had lost only one game in 13 since becoming Forest boss in September, but his Swansea successor Russell Martin said his return to south Wales would provide his players with an extra edge.

Both sides spent the first half at their most dangerous on the break.

Wing-backs Ethan Laird and Ryan Manning offered Swansea width in the final third, while the link play between Djed Spence and Johnson down Forest’s right flank was a constant threat.

Johnson showed his pace after robbing fellow Wales international Ben Cabango and Grabban was unable to convert his cross at the far post.

Another slick counter-attack saw Johnson and Spence combine to set up Zinckernagel, who was denied by Ryan Bennett’s brilliant block.

Swansea had created little with their 70 per cent-plus possession, but that was to change in a frantic period before the interval.

Forest dozed off from a Matt Grimes free-kick and the unmarked Olivier Ntcham sent a half-volley over the crossbar.

Ntcham was even more wayward moments later before Piroe wasted the best opening of the first period.

Jordi Osei-Tutu could only divert Flynn Downes’ long ball out of defence into the path of Piroe and the goal gaped with Brice Samba out of position.

But top scorer Piroe lifted the ball over as Samba desperately tried to retrieve his position.

Forest took a grip on the contest in a two-minute spell at the start of the second half as Zinckernagel capitalised on a poor Piroe header and won a 50-50 duel with Manning.

The Dane took a return pass from Grabban and beat Hamer inside his near post with a fierce drive.

Forest doubled their lead when Johnson burst onto Spence’s pass and crossed for Grabban to slide home at the back post.

Swansea halved the deficit after 62 minutes as Piroe’s powerful effort deflected off Ryan Yates for the Dutchman’s 12th goal of the season.

But Forest restored their two-goal advantage six minutes later when Hamer spilled Osei-Tutu’s tame effort and Johnson was on hand to prod in off the post.

Cafu lashed home Lyle Taylor’s pass in the dying seconds to confirm Forest’s move into the top-eight and seal Swansea’s third straight defeat.