Arsenal winger Gabriel Martinelli faces more than a month on the sidelines with a hamstring injury suffered during Wednesday’s EFL Cup loss at Newcastle United. Early indications suggest that is the duration Arsenal are set to be without the 23-year-old Brazil international. It would see Martinelli miss Premier League fixtures against Leicester City (February 15), West Ham United (February 22), and Nottingham Forest (February 26) — while also making him doubtful for the trip to Manchester United on March 9 and visit of Chelsea a week later on March 16. The Champions League round of 16 is...