The 24-year-old centre-back traded La Liga side Villarreal for North London during the January transfer window with striker Joel Campbell heading the other way on loan.
He arrived at the Emirates with the purpose of adding versatility and competition to the back four while also being pinpointed as a long-term replacement for the aging Per Mertesacker.
However, before Sunday there was little talk of Gabriel making a quick Premier League debut as concerns arose over his lack of English and possible difficulties in understanding key instructions.
An FA Cup encounter against Championship promotion hopefuls Middlesbrough was arguably as good as it could get in terms of easing him in.
And it ultimately proved a good decision by boss Arsene Wenger as two first-half goals from striker Olivier Giroud were enough to see the Premier League side comfortably over the line,.
According to stats provided by renowned statistical website Whoscored.com, Gabriel had a relatively calm afternoon alongside French centre-back Laurent Koscielny.
The Brazilian defender contributed with one tackle, two interceptions and eight effective clearances, though he was booked for a cynical foul which prompted a reaction from BBC pundit Pat Nevin.
"You have to remember that Gabriel is not 100% match fit at this level and it will take time,” he explained to the BBC.
“But he has been quite up and down so far. If there have been any problems in the Arsenal defence he has been at the heart of it."
In possession, the former Vitoria youth star demonstrated what he was capably of by producing 79 passes with an overall success rate of 93.7% - bettered only by his centre-back partner Koscielny.
Arsene Wenger will know that his new recruit will need time to bed in, but as far as debuts are concerned he certainly showed his capabilities and there are plenty of positives to take out of it.