Optics matter in the NFL. And last week, top Giants corner Deonte Banks looked like he quit running on CeeDee Lamb’s 55-yard Cowboys touchdown. So defensive backs coach Jerome Henderson lit up Banks’ apparent lack of effort on Friday morning. “Didn’t like it. Liked nothing about it,” Henderson said of Banks’ finish on the play. “When your man catches the ball, you have to break your legs — not literally, but figuratively — break your legs to get him on the ground for us. And I thought there was room to do more. “We expect [more] from him, and he expects it from himself,” Henderson added. “But he failed in that moment.” Head coach Brian Daboll did not bench Banks for his loafing. Banks was back on the field to start Dallas’ next drive playing outside corner, the same as always. But the corner’s dejected jog on that touchdown should be a major focus entering Sunday afternoon’s potential bloodbath against the Seahawks (3-1), which the Giants (1-3) must play without top offensive weapon Malik Nabers (concussion). Because Seattle quarterback Geno Smith led the NFL in passing yards entering Week 5. And D.K Metcalf, Jaxon Smith-Njigba and Tyler Lockett comprise one of the league’s top receiving corps. So it’s going to be a long day for defensive coordinator Shane Bowen, Banks and the Giants’ secondary in particular. And if the score gets out of hand, Sunday’s primary question will be whether Banks’ lackadaisical Week 4 approach will become contagious. There is no worse reflection on GM Joe Schoen and Daboll than a player not giving full effort on the field, not to mention one of the GM’s first-round picks. Banks, 23, owned up to his mistake on Friday. “It was a bad finish by me,” the second-year corner said. “I didn’t really feel it in the game. But [after watching the film, I realized] I could have definitely finished more. I maybe could have even tackled him. But we’re past it now.” “In the game, I thought it was like an angle thing,” he added. “I didn’t think it was an effort [issue] until I saw the film. It looked like, ‘Oh, I could [have] had it. I could have done more.’” While there is no excuse for less than 100% effort, however, Banks’ frustrating situation is born out of this team’s poor construction and plan. Banks at best should be a No. 2 corner on an NFL defense right now, but Schoen and Daboll have shoved him into a No. 1 role to take on and travel with the league’s top receivers every week. So his responsibilities are greater than his ability at this point in his career. And the results so far speak for themselves. Banks’ shoulder slumping, in fact, seemed to be a direct result of cumulative frustration about his own on-field results in these mismatches. He allowed three touchdowns in the first three weeks: one to Minnesota’s Justin Jefferson and two to Cleveland’s Amari Cooper. And he told the Daily News that he felt like “I played like some s–t” against the Browns. That was an especially difficult game because at some point in the second half, Cleveland coach Kevin Stefanski obviously decided to attack Banks consistently in particular. Banks is tough-minded, but he noticed that the Browns believed he was an area to exploit. Then in Week 4 he got burnt by Lamb, who dodged rookie safety Tyler Nubin’s poor angle. And suddenly Banks was slowing up as Dallas’ best player coasted into the end zone and fired the ball back at him in celebration. Daboll was not asked about Banks’ apparent lack of effort. Banks came off the field for two snaps late in the Dallas game, the first snaps he has missed all season. But that seemed to be Bowen’s personnel adjustment when the Cowboys went with a jumbo formation and no outside receivers. Cor’Dale Flott and Nick McCloud played those two run downs. Henderson said he spoke to Banks immediately on the sideline last week after the disappointing play. “Oh yes, absolutely,” Henderson said. “I’m certain [the message] was delivered. I think it was received. We’ll see.” It might help Banks, of course, if he isn’t asked to travel with the opponent’s best receiver all over the field every week. Henderson implied the Giants may make that adjustment in Seattle. “Well, we’ll see this week if he travels,” Henderson said. “We’ll see how this game plays out and what the plan is this week. But every week we’re kinda looking at matchups, who’s the best fit … And it changes a little bit every week.” No matter how the coaches deploy Banks, however, there is no excuse for a lack of effort. “Anytime your man catches the ball, especially when your man catches the ball, get him on the ground,” Henderson said. “Get him on the ground. Let us play one more snap. Give us a chance to go have a goal line stand. You owe that to the team, you owe that to the organization, and it’s my job to get him to do it.” Sunday’s expected blowout should reveal whether Banks’ loafing was the start of a trend, though, or if it was a one-off mistake by a young player. For Schoen’s and Daboll’s sakes, they’d better hope it was the latter.