When coach Jeff Fisher threw out the red challenge flag late in the second quarter Friday night, there couldn’t have been many in the Edward Jones Dome who thought Rams cornerback E.J. Gaines had stopped Saints wide receiver Nick Toon short of the first-down marker. Actually, neither did Fisher. “No, I thought it was a good spot,” Fisher said. “I was standing right there.” So why did he make the challenge? Basically, Fisher was doing a favor for referee Carl Cheffers and his crew. “(Friday) was the first time that this crew was gonna potentially communicate with New York,” Fisher said. Last March, club owners approved a change in the replay system, allowing the league’s officiating headquarters in New York to have input on replay challenges to crews. “So I just said if there’s anything close, I’ll go ahead and challenge it for you and see how it goes,” Fisher said, referring to Cheffers. As expected, the call was upheld, the Saints got their first down, and as a result of the unsuccessful challenge the Rams were charged a timeout. It’s a timeout the Rams could’ve used in the final 2½ minutes of the half with their offense on a drive that started at the St. Louis 8 and ended with a 45-yard field goal by Greg Zuerlein as the half expired.