Captain Sean Morrison celebrated in front of around 2,500 Cardiff City at the KCOM Stadium in Hull.
Centre-half Morrison scored both Bluebirds’ goals in a 2-0 win which keeps them on course for automatic promotion to the Premier League.
A win against relegation battlers Reading at Cardiff City Stadium next Sunday will ensure manager Neil Warnock and his team play top flight football against the likes of Manchester City, Liverpool and Spurs next season.
Wolves are champions and already up, while the battle for the second automatic spot is a straight shootout between Cardiff and Fulham.
The London club are one point behind City and travel to play Birmingham City on Sunday.
Warnock’s men have the advantage and cannot be stopped if they win – and what a night it would then be at Cardiff’s club awards night in the evening.
City were rocked when Aaron Gunnarsson suffered an early injury with Mark Grujic taking over, but the young Serbian player was booked and then given a final warning by the referee for two fouls.
Warnock decided to act and replaced sub Grujic with Craig Bryson for the second half.
“Fantastic, what a great result,” said former Cardiff City captain Kevin Ratcliffe on BBC Wales radio. “Sean Morrison scored two different goals – the first a header from a corner and his second on a breakaway.
“What was he even doing in Hull’s penalty box? But Morrison got the ball, showed the composure of a striker and picked his spot. When that went in everybody was off the Cardiff bench celebrating.
“Cardiff had top work hard for it. They looked a little unsettled after Aaron Gunnarsson went off with what looked quite a serious knee injury, but the first goal settled them again.
“If Cardiff players can handle the nerves at home in front of a full house they are more than capable of winning against Reading. There will be a lot of pressure, but when a great day for the club.”
Junior Hoilett and Joe Ralls were outstanding for Cardiff in another huge team performance.
Hull included former Bluebirds players Fraizer Campbell and goalkeeper Allan McGregor, but they were second best.
Cardiff goalkeeper Neil Etheridge scarcely had a shot to save, while Morrison was a leader at the back alongside Sol Bamba and in attack.
His first goal was a header into the roof of the net from a Ralls corner after 32 minutes, when his second came out of the blue.
Hull were pressing hard when Lee Peltier bravely blocked a shot with his chest and the ball ran for Nathaniel Mendez-Laing. The winger burst forward, producing skill and pace to go away from a defender.
Mendez-Laing picked out lone striker Kenneth Zohore, who showed great awareness to spot Morrison’s run forward.
The big defender took a touch with his right, pulled the ball inside and drilled his shot home to make his tally for the season to seven.
That came with 10 minutes left and the Bluebirds eased their way to victory.
The Tigers had lost just one of their last nine home league matches against Cardiff, but this was a day when the Welsh club dominated and earned the points they needed.
Zohore ran and chase in his attack, hassling defenders and giving centre-half Michael Dawson a torrid time. He was playing a lone role and went off after 90 minutes with Gary Madine taking over.
Next Sunday’s Championship fixtures all kick-off at 12.30pm and Cardiff simply have to match or beat Fulham’s result.
Manager Slavisa Jovanovic and his Fulham team are unbeaten in their last 23 matches, but will miss out if Cardiff beat Reading.
Fulham face the prospect of finishing on 91 points with a win against Birmingham City away and could yet become the first team to top the 90 mark and miss out on automatic promotion.
Hull City: McGregor, Aina, Dawson, MacDonald (Mazuch 14), Kingsley, Wilson, Henriksen, Meyler, Grosicki (Toral 73), Keane (Bowen 66), Campbell. Subs not used: Irvine, Dicko, Marshall, Tomori.
Cardiff City: Etheridge, Peltier, Morrison, Bamba, Bennett, Paterson, Gunnarsson (Grujic 10, Bryson 46), Ralls, Mendez-Laing, Zohore (Madine 90), Hoilett. Subs not used: Manga, Pilkington, Murphy, Ward.
Referee: Andy Davies
Attendance: 17,441
Championship 2017-18
Current table
| | HOME | | AWAY | |||||||||||||
| P | W | D | L | F | A | W | D | L | F | A | GD | PTS | ||
| 1 | Wolves | 45 | 16 | 5 | 2 | 47 | 18 | 14 | 4 | 4 | 35 | 18 | +46 | 99 (C) |
| 2 | Cardiff | 45 | 16 | 3 | 3 | 40 | 16 | 11 | 5 | 7 | 29 | 23 | +30 | 89 |
| 3 | Fulham | 45 | 13 | 8 | 2 | 40 | 17 | 12 | 5 | 5 | 38 | 26 | +35 | 88 |
| 4 | Aston Villa | 45 | 14 | 7 | 2 | 42 | 19 | 10 | 4 | 8 | 30 | 22 | +31 | 83 |
| 5 | Middlesbro | 44 | 13 | 3 | 6 | 31 | 17 | 8 | 6 | 8 | 32 | 26 | +20 | 72 |
| 6 | Derby | 45 | 11 | 5 | 6 | 37 | 21 | 8 | 10 | 5 | 29 | 26 | +19 | 72 |
| 7 | Preston | 45 | 8 | 8 | 6 | 25 | 21 | 10 | 8 | 5 | 30 | 24 | +10 | 70 |
| 8 | Millwall | 44 | 11 | 7 | 4 | 32 | 21 | 7 | 8 | 7 | 23 | 22 | +12 | 69 |
| 9 | Brentford | 45 | 9 | 10 | 3 | 36 | 23 | 9 | 4 | 10 | 25 | 28 | +10 | 68 |
| 10 | Bristol C | 45 | 11 | 6 | 5 | 39 | 25 | 6 | 10 | 7 | 26 | 30 | +10 | 67 |
| 11 | Sheff Utd | 45 | 12 | 5 | 6 | 33 | 20 | 7 | 4 | 11 | 26 | 33 | +6 | 66 |
| 12 | Norwich | 45 | 8 | 8 | 7 | 25 | 25 | 7 | 7 | 8 | 23 | 30 | -7 | 60 |
| 13 | Ipswich | 45 | 9 | 5 | 8 | 27 | 25 | 8 | 3 | 12 | 28 | 33 | -3 | 59 |
| 14 | Leeds | 45 | 9 | 6 | 7 | 30 | 27 | 7 | 3 | 13 | 27 | 37 | -7 | 57 |
| 15 | QPR | 45 | 12 | 5 | 6 | 38 | 31 | 3 | 6 | 13 | 20 | 37 | -10 | 56 |
| 16 | Sheff Wed | 45 | 7 | 7 | 8 | 32 | 30 | 6 | 8 | 9 | 22 | 29 | -5 | 54 |
| 17 | Nottm Forest | 45 | 10 | 3 | 10 | 25 | 27 | 5 | 5 | 12 | 24 | 35 | -13 | 53 |
| 18 | Hull | 45 | 7 | 8 | 8 | 41 | 32 | 4 | 7 | 11 | 28 | 37 | 0 | 48 |
| 19 | Reading | 45 | 5 | 8 | 10 | 25 | 35 | 5 | 5 | 12 | 23 | 35 | -22 | 43 |
| 20 | Birmingham | 45 | 9 | 3 | 10 | 18 | 23 | 3 | 4 | 16 | 17 | 44 | -32 | 43 |
| 21 | Barnsley | 45 | 5 | 9 | 9 | 25 | 32 | 4 | 5 | 13 | 22 | 36 | -21 | 41 |
| 22 | Burton | 45 | 4 | 5 | 14 | 19 | 43 | 6 | 6 | 10 | 18 | 36 | -42 | 41 |
| 23 | Bolton | 45 | 8 | 4 | 10 | 22 | 31 | 1 | 9 | 13 | 14 | 41 | -36 | 40 |
| 24 | Sunderland | 45 | 2 | 7 | 13 | 20 | 39 | 4 | 9 | 10 | 29 | 41 | -31 | 34 (R) |