EAST RUTHERFORD, N.J.—Sean McVay wasn’t happy walking into the postgame news conference after his Los Angeles Rams had their way with the banged-up and struggling New York Giants. Despite getting another big game from quarterback Matthew Stafford and receiver Cooper Kupp, and four takeaways from his defense, McVay didn’t enjoy the opening quarter of the Rams’ 38-11 win on Sunday. The problem was, McVay’s team had a slow start. It’s not the first time this season, but when you’re 5-1, coaches expect a lot. “I think we can be a lot sharper offensively,” McVay said of being shut out in the first quarter. “We’ve got to start faster. There’s no excuse. We got to be better than that. We’ll take the win and I thought our guys did a nice job today.” The Rams were very good in the second and third quarters in taking a 38-3 lead over the …