Mikel Arteta has now praised one Arsenal ace who ‘stepped up’ in the Gunners’ 5-0 thrashing of London rival Chelsea during Tuesday night’s win in the Premier League. The north London giants showed the clear gap in quality between Arteta’s title-chasing team and Mauricio Pochettino’s billion-pound side. Goals by Leandro Trossard (4’), Ben White (52’, 70’) and Kai Havertz (57’, 65’) broke Chelsea as Arsenal, who should have had more, ran riot. Arsenal now sit three points above Liverpool, who visit Everton this Wednesday night, at the top of the table. Three-time defending Premier League champio…