And the Spanish-born art director and designer looked in good spirits as her other half geared up for his first taste of the north London derby on Saturday.
Grassi posted the picture above of herself with a beaming smile on Instagram on Saturday morning, along with the message: “Happy Saturday.”
Arsenal fans will be hoping that Sánchez will be just as happy after the final whistle at Emirates Stadium on Saturday evening.
The Chile international has scored two Premier League goals in four games for Arsene Wenger’s men so far this season after joining the Gunners from Barcelona for £35m in the summer.
He also hit a stunning free-kick in the 2-1 League Cup defeat by Southampton in midweek, after netting his first Arsenal goal against Besiktas in the Champions League play-off in August.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news