Two late goals saw Norwich City fall to defeat at the Cardiff City Stadium, despite leading through Borja Sainz's brilliant opener.
Johannes Hoff Thorup was forced into a number of changes from the team that began the home fixture against Middlesbrough.
Oscar Schwartau, Gabriel Forsyth and Jacob Sørensen replaced Kenny McLean, Anis Ben Slimane and Josh Sargent in the starting line-up.
The first clear opening fell the way of Cardiff City after 13 minutes as Ollie Tanner wriggled past Callum Doyle, but his cross was put wide of George Long's near post by Chris Willock.
Borja Sainz beat his man and burst down the left wing on 18 minutes but Emi Marcondes couldn't get on the end of his cross.
On 21 minutes, a well-worked free kick saw Shane Duffy meet a cross from Schwartau but the City defender's firm header was well wide.
Sainz turned brilliantly near halfway and drove forwards before unleashing a low drive that was beaten away by Jack Alnwick on 23 minutes.
After 26 minutes Marcondes went close as his shot was blocked behind for a corner, which he brilliantly whipped into a dangerous area somehow evading every player in the box.
Some neat football in the 37th minute gave Ante Crnac, playing up front in place of the absent Sargent, a chance but his shot was blocked well. The resulting corner was knocked down by Duffy to Schwartau whose double effort was blocked and Cardiff escaped after a foul.
Cardiff started brightly after the break and Forsyth was needed on 49 minutes to block a shot from Rubin Colwill from the edge of the box.
Norwich made the breakthrough after 52 minutes with another moment of brilliance from the in-form Sainz. Doyle did well to control a clearance and supply the Canaries winger, whose shot from outside the area beat Alnwick for his 11th of the season.
David Turnbull's shot from distance was beaten away well by Long in the 57th minute as Cardiff looked to respond.
Duffy met a corner at the back post after 60 minutes but his powerful header was straight at Alnwick.
In the 67th minute, Crnac found Sainz but his shot was saved by Alnwick, before substitute Jack Stacey's follow up was blocked on the line.
Crnac flashed a shot from outside the box narrowly past the near post of Alnwick in the 84th minute.
Cardiff City equalised in the 89th minute as Callum Robinson's shot was cruelly deflected past George Long.
Callum O'Dowda broke Norwich hearts in the third minute of stoppage time with a fine strike from the edge of the area to win it for the home side.
Cardiff City: Alnwick (C); Rinomhota (Daland 83), Goutas, Chambers, O'Dowda; Siopis, Turnbull, Tanner, El Ghazi (Robinson 62); R Colwill, Willock (Ashford 76).
Unused subs: Horvath, Fish, Bagan, Meite, Reindorf, Kanga
Goals: Robinson (89), O'Dowda (90+3)
Bookings: Rinomhota (45+1), Turnbull (54), O'Dowda (78)
Norwich City: Long; Fisher (Chrisene 63), Duffy (C), Córdoba, Doyle; Sørensen (Forson 75), Forsyth (Stacey 63), Marcondes; Schwartau (Hanley 75), Sainz, Crnac (Gordon 86)
Unused subs: Mair, Mahovo, Springett, Fassnacht
Goals: Sainz (52)
Bookings: Fisher (42), Córdoba (82)
HT: 0-0
FT: 2-1
Venue: Cardiff City Stadium
Referee: Lewis Smith
Attendance: 19,032