Sergio Busquets got an early goal for the Catalans before they had Dani Alves sent-off early in the second-half.
Ruben Castro took full advantage of the numerical difference to score twice for Betis in the final 20 minutes, leaving Guardiola staring at defeat until Seydou Keita headed in an equaliser in the dying moments.
Guardiola’s final game will be on May 25 when his side take on Athletic Bilbao in the Spanish Cup final.
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