The 21-year-old watched on from the stands as Chelsea earned a controversial 2-0 Premier League win over Fulham just ahead of his move.
Garnacho was spotted scrolling on his phone just minutes after kick-off, something that Liverpool legend Jamie Carrgher took offence to.
"You know what I didn't like?" he said on the Overlap podcast. "Did you see the game (against Fulham), when they go to the people in the stands and they are on their phones with the game going on?
“I can't stand it. And it's not just him by the way, but I can't stand it. So it's a miss for that. For sitting on his phone during an important game for Chelsea."
The young winger is currently training at his new club having missed out on a place in the Argentina squad for their World Cup qualifiers against Venezuela and Ecuador.