The record was set during his La Velada Del Año II boxing event at the weekend that featured multiple content creators in the ring.
The previous record was set by TheGrefg at 2.5m concurrent viewers.
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What’s more, Ibai is now in the top five most followed streamers on Twitch.
The event brought over 400k new followers, bringing his total followers to over 11m (Ninja remains at the top with 18m).
The record proves the popularity of Spanish-speaking streamers on the platform. The event was also the second of its kind from Ibai - his first La Velada Del Año event peaked at 1.5m concurrent viewers.
Ibai rose to fame on Twitch by commentating on esports. He’s also interviewed a number of top Spanish footballers on his channel including Gerard Piqué, Andrés Iniesta, Ronaldinho, Sergio Agüero and Sergio Ramos.