Chelsea had floundered for 45 minutes and were deservedly behind at the break after Isco, who ran the opening period, delivered a no-look assist to tee up Abde Ezzalzouli before he powered in the opener inside nine minutes.
The turnaround win in Poland justified after Enzo Maresca has decided to subsititute Malo Gusto and replace him by Reece James from the first whistle of the second half.
With the Blues 25 minutes away from defeat in Wroclaw, Cole Palmer turned on the class to set up goals for Enzo Fernandez and Nicolas Jackson with crosses from the right.
Fernandez nodded in from Palmer’s inswinger and Jackson then bundled in with his chest at the near post five minutes later.
Jadon Sancho made it comfortable with a lovely curling finish from fellow substitute Kiernan Dewsbury-Hall’s pass in the 83 minutes and Moises Caicedo added a fourth in injury time with a deflected effort from 20 yards out.
Chelsea’s win against Real Betis in the Conference League final makes the Blues the first team to win all five Uefa club tournaments – the Champions League, Europa League, Conference League, Super Cup and the defunct Cup Winners’ Cup.
And it brings to an end a remarkable run – with Chelsea the first foreign team to beat a Spanish side in a final since 2002.
Chelsea’s season is not finished though, as they start their Fifa Club World Cup campaign in mid-June in the United States.
Player ratings
Chelsea: Jorgensen (6), Gusto (4), Badiashile (5), Chalobah (6), Cucurella (6), Fernandez (7), Caicedo (7), Neto (5), Palmer (9), Madueke (6), Jackson (7).
Subs: James (7), Sancho (7), Colwill (6), Dewsbury-Hall (7), Guiu (n/a).
Player of the Match: Cole Palmer.
