Four weeks into the 2019 season, the first with Hall of Fame coach Mack Brown back on the sideline with North Carolina, and it feels like the Tar Heels have already experienced a season's worth of twists and turns. Preseason expectations for this group have been set, adjusted, readjusted and reset during a 2-2 start that kicked off with wins against South Carolina and Miami before the Tar Heels suffered losses to Wake Forest and Appalachian State.

On paper, that's a wide variance in opponents, but all four games have featured a similar conclusion: North Carolina either needing a stop or a score at the end of the fourth quarter to win. 

The gloomiest projections for the Tar Heels saw those four games, and Saturday's upcoming contest against No. 1 Clemson, as potential or likely losses. And while North Carolina has proven itself as a far more competitive team than foretasted, Brown knows that his team is just as close to being 0-4 as it is to being 4-0. 

"We've played well enough to beat four teams. We could have lost all four games, but we could have won all four games. What we've told the guys is our identity needs to be not coming back in the fourth quarter like we've done the last two weeks, but it needs to be winning in the fourth quarter and finishing the game off like we did the first two weeks," Brown told CBS Sports. 

Searching for consistency has been both an opponent-to-opponent and quarter-to-quarter issue for the Tar Heels. Brown has identified the second quarter -- North Carolina has been outscored 41-13 in that quarter this season -- as well as the team's struggles at pivot points within a game -- as particularly troubling.

"We've got to start understanding that there are key plays and key moments in the game, and we've got to start making them," Brown said. 

That Brown finds this roster lacks understanding should not come as a surprise. Though North Carolina has won only five total games over the last two seasons, but it wasn't an uncompetitive team. Nine of the 18 losses in that span were one-score defeats, and throughout those frustrating results was a common thread of penalties, mistakes and missed opportunities in key moments of the game. The Tar Heels often struggled to respond to adversity, the type of responses that leads to wins for more established teams. Reversing whatever mental and emotional muscle memory lingers from those close losses is a part of the challenge for Brown and his staff. 

Perhaps the most impactful arrival to North Carolina football outside of Brown himself is true freshman quarterback Sam Howell. The 6-foot-1, 225-pound rookie from Monroe, North Carolina, flipped from Florida State to UNC and joined the program during the early signing period, shortly after Brown was announced as the new coach. As the No. 2 in-state player, Howell's arrival was treated with fanfare as a big-picture recruiting win for a program that is constantly going head-to-head with out-of-state name brand programs for the best local talent. 

Howell was given a decent chance to be North Carolina's starter based on his upside and the health of the quarterback room that Brown and offensive coordinator Phil Longo inherited. The unknown was how this young blue-chip prospect would handle the jump from 3A ball in the Charlotte metro area to big-time college football against the likes of South Carolina, Miami and Clemson. From the season opener onward, Howell has shown a poise and fearlessness on the field that extends beyond any outside expectations. 

The difference between 2-2 and 0-4 is Howell, and the confidence and toughness that he adds to the roster can go a long way in reversing some of the habits from the close losses of the previous era.  

The strive for consistency and Brown's work to help North Carolina establish a new standard for performance is not limited to the players. Throughout the highs and lows of this roller coaster season,  Brown has been just as critical of himself and the coaching staff as he is of the players. One of the unique advantages to being a national championship-winning, Hall of Fame coach returning to the sideline is the opportunity to coach the coaches. 

"I've got more experience than anybody on our staff. I've been at this school longer than anybody on our staff. Most coaches have trouble being as direct as they need to with their staff some because they're friends or they've been around a long time. You don't want to hurt the guy's feelings, and you don't want him to leave," Brown explained. "Very honestly, what I'm going to do is I'm going to coach the coaches just like I coach myself and just like I coach the players. 

"I'm going to be direct. It's going to be harsh. It's going to be professional. But if a coach isn't doing his job, I have the responsibility to make sure our coaches are giving our players an advantage over the team that they're playing, or why do you need the coach? Sometimes assistant coaches just like their job and want to be around, but their job is help their players beat the other guy."

While the ups and downs of Brown's 2-2 start in his return to North Carolina have provided plenty of entertainment and exceeded the expectations of many outside the program, the push for consistency and establishing an identity remains a work in progress. Following the loss to Wake Forest, players recognized that their poor start -- a 21-0 first half deficit in that 24-18 loss -- was tied to looking down on the opponent after its 2-0 start. 

"We didn't come out with the energy we were supposed to. … We thought we had better players," linebacker Jeremiah Gemmel told Inside Carolina. "We thought we were the better team coming in."

Brown noted in his postgame comments that the team wasn't "mature enough," and he took some blame along with the coaching staff for not getting the Tar Heels emotionally ready following the win over Miami. He knows that the key to real, lasting success for North Carolina football isn't going to be a few big wins but instead getting the Tar Heels to a place where the energy, the effort and the performance is matched every time they take the field. 

"What I expect of our players is start living up to a standard for us," Brown explained earlier this week. "We can't play South Carolina any different than we play Clemson. We can't play Appalachian any different than we play Clemson. What we need to do is worry about us, and that way you don't play up and down to the opponent each week."

Since North Carolina's players have responded well to being the underdog, Clemson should expect a similarly motivated and energetic effort on Saturday in Chapel Hill. But Brown seems just as concerned about how his team is going to play the next at Georgia Tech and throughout the rest of the Tar Heels' schedule.

Establishing consistency regardless of opponent and winning those key moments in games is going to be crucial if the Tar Heels want to build on the success of this early season.