LONDON, Dec 3 : Arsenal re-established their five-point lead at the top of the Premier League with a 2-0 home win against Brentford on Wednesday and for the second evening running the goals flowed as Aston Villa won 4-3 in a thriller at Brighton and Hove Albion. Mikel Merino's 11th-minute header gave Arsenal the lead but they needed a stoppage-time goal by substitute Bukayo Saka to make the points safe on a night of hard graft in which they stretched their unbeaten run in all competitions to 18.