DALLAS — The Dallas Cowboys fell to the San Francisco 49ers 17-9 in the preseason opener at Levi's Stadium in Santa Clara, Calif., on Saturday night. While it was a team effort in the loss, as is the case when trying to get 90-man rosters to compete in exhibition games, there were three Cowboys who didn't turn in favorable performances.

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QB Mike White

The former 2018 fifth-round pick from Western Kentucky was the signal caller for the third-string offense, so his stat line of 9-of-20 for 87 yards is understandable. However, he showed some indecision on throws and also poor fundamentals when he was sacked and lost a fumble. 

White had the right instinct to get out of the pocket on first-and-10 from the Dallas 18 with 5:13 to go in the third quarter. However, he didn't protect the football as he was escaping, and that allowed safety Antone Exum to strip the ball from White's grip. 

The Cowboys would be in trouble if White ever had to play in a regular season game regardless, but it's this type of play that demonstrates the gap widening between second-string quarterback Cooper Rush, who was 16-of-26 for 142 yards, and White. 

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How that impacts the Cowboys' decision to keep three quarterbacks remains to be seen, and could be affected by the versatility of other players.

TE Dalton Schultz

Things got easier for Schultz when the club said goodbye to Rico Gathers, but Schultz is still a part of the tight end group that was affected when Jason Witten decided to return. Schultz had a pass hit him in the hands on third-and-6 from the Dallas 14-yard line with 4:35 in the second quarter, and he finished the game with two catches for 13 yards. 

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Was he ever really a threat to overtake Blake Jarwin as the second tight end on the roster, or maybe even Witten if the future Hall of Famer fell to TE2 on the depth chart? Probably not, but it closes the gap between himself and Marcus Lucas and Codey McElroy, who had two catches for 24 yards. Schultz needs to rebound from his first game showing and put more distance between himself and the other two tight ends.

K Brett Maher

The "other boy" who replaced Dan Bailey last season missed a 35-yard field goal with 8:30 in the second quarter. Last season, Maher had an 80.6% field goal percentage and missed just one extra point, which is the comparable distance for Maher's missed field goal Saturday night. With no competition on the roster, the Cowboys could enter 2019 with a kicker crisis. Consider the distance Maher missed: 35 yards, or the 17-yard line, or more specifically, the red zone. 

If Dallas is as atrocious in the red zone as they were last year, when they had the fourth-lowest conversion rate in the NFL at 48.0%, then Maher cannot fall below his 75.0% accuracy (6-of-8) on field goals in the 30 to 39-yard range, not to mention missing extra points. 

The Cowboys had some breaks go their way while rebounding from a 3-5 start and finishing 10-6 on their way to winning the NFC East in 2018. Maher missing field goals in the red zone is part of the "bad luck" that can put ball games in the other side of the W-L column for Dallas this season.

Do you think the Cowboys will be able to compete for the NFC East title again in 2019? Share your thoughts on the team with Mark on Twitter @therealmarklane after seeing them in action on Saturday.