lay in Sean Lee’s absence In a weekend that saw the Philadelphia Eagles Dallas Cowboys T-Shirt , Washington Redskins, and New York Giants all fall, the Dallas Cowboys were unable to take advantage and stake their claim in the NFC East. Fortunately, their 2-3 record will not keep them out of the hunt, but it was certainly a missed opportunity that leaves a bad taste in the mouths of Cowboys fans.The offense struggled to get into the end zone, which is already a common theme through five games this season. The defense, meanwhile, allowed Deshaun Watson, DeAndre Hopkins, and company move down the field, only to stiffen up in the red zone. While the defense did not play exceptionally well all night, they certainly appeared to have played well enough for a win.Let’s take a look at how the rookies performed on the big stage on Sunday Night Football in week five.Leighton Vander EschLeighton Vander Esch has seemingly been playing with a chip on his shoulder since taking the field for the Dallas Cowboys in his first season. Maybe it is because he remembers the fan reaction when Dallas selected him in AT&T Stadium. Maybe it is because he wants to prove that a former eight-man football player can not only play — but succeed — on the highest level. Maybe he is just good at football?Whatever the case is, LVE has been playing at an exeptional level for this defense since week two, where he played approximately 20 snaps and made seven stops. Vander Esch followed that up with impressive outings in a loss versus the Seahawks in Seattle and again in a victory over the Lions back at home in week four.The talk has been surrounding Jaylon Smith — who had himself a solid game in his own right as he flew all over the field — but Vander Esch did not disappoint against Houston, either. The Boise State Broncos product led the team in tackles with 11 during the Sunday Night Football overtime loss, nine of which were solo. Whatever your feeling was when the Cowboys selected him back in May, Vander Esch appears to be a stud at linebacker for America’s Team.Connor WIlliamsSome Cowboys fans were more thrilled about the Connor WIlliams pick than the LVE pick, as the Texas Longhorns product had some first-round hype with his ability to play different positions across the offensive line. With the hole at left guard, Williams would seemingly be an ideal fit next to Tyron Smith and Travis Frederick.While Frederick has yet to play a regular season snap in 2018 Dallas Cowboys Hats , Williams has had to hold his own against quality defensive fronts over the course of his first month on the professional level. Williams had his ups and his downs, allowing sacks and QB pressures, but also beinga solid blocker for Ezekiel Elliott in the run game.Williams was called for a critical (and controversial) holding call on big Zeke run that looked to give Dallas some momentum on Sunday evening. It was a call that hurt the Cowboys offense from gaining traction in an eventual loss.Michael GallupThe need for playmakers, other than Zeke, on the Cowboys offense is evident. Dak has struggled, the play-calling has raised eyebrows, and the offensive line has struggled without Frederick manning the middle. There was a lot of hype surrounding the team’s third-round selection, but Gallup has yet to really make an impact with the Cowboys through five games this season. He drew some PI’s in week one and made that 37-yard grab in week four, but other than that?Gallup grabbed one pass for six yards — but, in fairness, the rookie may have had a little more to his total on this play, had things gone right:Whether it be the quarterback, the receivers, or the coaching staff (or all three), this passing game simply cannot get going. Will Gallup be able to make an impact before season’s end?Dorance Armstrong Jr.Dorance Armstrong Jr. is behind a loaded defensive end unit in Dallas, but the Kansas Jayhawks rookie has shown some potential with the snaps that he has received over his first five games with the Cowboys. Armstrong was able to find his way into the box score during his limited snaps, making one stop on the night. The rookie also saw some snaps at the 3-tech during the game on passing downs. It will be interesting to see how the staff uses the 6-foot-4, 257-pound defensive lineman moving forward. Watching Patrick Mahomes this season has made Tom Brady feel like an old man.At least old enough to remember a much different era for young NFL quarterbacks.As a rookie in 2000, Brady remembers being nowhere near seeing the field as a starter."I was sitting in the stands Dallas Cowboys Hoodie , eating nachos before games. I wasn't playing," he joked this week.Now he looks around at a league in which Mahomes is one of several young quarterbacks in their first or second year starting for teams. Brady also started his second season, but it was hardly the plan as he replaced an injured first stringer, Drew Bledsoe."Football was different then," Brady said. "I think now in some ways pro football is more glorified college football...the transition is a more similar game than it used to be when I first started."It's an atmosphere that has allowed Mahomes, who will be starting for Kansas City when the Chiefs (5-0) visit New England (3-2) on Sunday night, to emerge as the most electrifying quarterback in the NFL this season.Mahomes leads the NFL with 14 touchdown passes through Week 5 and has won each of his first six NFL starts, dating back to his lone start last season. With a win against the Patriots, Mahomes would become the sixth quarterback since 1970 to win his first seven career starts.It's put the second-year Texas Tech product under the microscope in his first year Kansas City's full-time starter, following the offseason trade of Alex Smith to Washington.While Mahomes said running the jet sweeps and run-pass option plays he did in college has helped with his transition, he also spent a fair amount of time studying Brady's approach in New England."My coach in college was Kliff Kingsbury, and he actually was a backup for Brady at one point, and so he showed me things that he liked with Tom and his pocket movements and stuff he did within the pocket that I've tried to put in my game a little bit," he said.While Chiefs coach Andy Reid won't disparage Smith, he acknowledges Mahomes brings a lot of intangible qualities to their offense. Reid also is cognizant that the season is still young.The 23-year-old is not a rookie, but he basically is, Reid said."He's going through an NFL season — his first one — and there are all kind of challenges that come with that, and no bigger one than this week," Reid said.Here are some things to watch for in Sunday night's game:NOT AN UNDERDOGDespite Kansas City's unblemished record Customized Dallas Cowboys Jerseys , the Patriots enter Sunday's game as a three-point favorite. It's for good reason. Since 2001, 41 times a team has visited Foxborough with a better record than the Patriots. In those games New England is 30-11.Since starting the season 1-2, New England has outscored opponents 76-31 over its last two victories, at home vs. Miami and Indianapolis.MILESTONE WATCHBrady has an NFL-record 199 career regular-season victories and can become the first quarterback in league history to reach 200 for his career. He enters this week tied with Colts kicker and former teammate Adam Vinatieri for the most career wins in the regular season and playoffs combined with 226.BRING THE NASTYThe Chiefs' maligned defense forced Jacksonville into five turnovers last week, not to mention showed a mean streak for the first time all season. Defensive tackle Chris Jones took it a bit too far, getting ejected for throwing an elbow at a Jaguars lineman after a play."I don't even remember what happened," Jones said with a wry smile. "But we're not going to let anyone push us around."INJURY WOESThe Chiefs signed ex-Browns linebacker Nate Orchard and journeyman Frank Zombo to help with pass-rushing depth. Justin Houston has a hurt hamstring, and fellow pass rushers Dee Ford and Tanoh Kpassagnon have been banged-up, which left only rookie Breeland Speaks available."Tanoh will have a chance to play," Reid said, "but we just have to make sure we are OK in that spot just in case."MATCHING WITSThe game features the two winningest active coaches in Bill Belichick (281) and Reid (199); Belichick is 5-2 lifetime against Reid. "I mentioned this before," Reid said, "when you play good football teams, you love that challenge. You spend a lot of hours doing what we are doing. You love the challenge of it, and I think as players and coaches you cherish those things. It is a neat part of the business."AP Sports Writer Dave Skretta contributed to this report.