The 25-year-old, who missed Wednesday’s 4-2 win over Reading after Luiz cited a knee injury on Twitter, travelled to the Spanish city to watch Barcelona’s Super Cup first-leg showdown with Real Madrid at Camp Nou.
His trip appeared ill-timed as reports emerged suggesting the La Liga outfit are plotting a £30m bid for the defender at around the same time he posted a picture of himself on a luxury plane and Tweeted: “Going to #barcelona See you soon…”
But Di Matteo insists he was simply fulfilling his sponsorship dutues and says the Brazil international has not been fined for causing a stir on the social network.
“He went to a sponsor event with a sponsor,” said Di Matteo. “In modern-day football, players have sponsorship deals and as long as it doesn’t affect their performance, you try to obligate those duties.
“No [he has not been fined]. Generally we don’t fine our players for Tweeting. We remind them of the responsibilities they have because obviously it’s a vehicle that can be read by everybody. But we don’t discourage our players from using it.”
And when asked if Luiz is still an important player for the Blues, Di Matteo replied: “Very much, yes”.
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