They proved that their defense was just as dominant as it was last season.
They proved that Matt Schaub and Andre Johnson had not missed a step despite missing many games due to injuries last season.
They proved that they are a team to be reckoned with.
The Texans, however, left many unanswered questions on the field.
Is the run defense an issue? Will the offensive line hurt the offense? Will Trindon Holliday produce this season?
Here are the biggest questions left unanswered about the Texans after Week 1.
The Texans less than stellar run defense versus the Dolphins should be a concern for every Texans fan.
In the preseason, opposing offenses were able to exert their will against the Texans on the ground. The San Francisco 49ers, the Minnesota Vikings and the New Orleans Saints were all able to gain huge chunks of yardage versus the vaunted defense.
Many blamed the poor performance of the defense on the Texans' missing starters—Brian Cushing, J.J. Watt and Shaun Cody. Certainly all three of those players contribute heavily to the Texans' run-stopping efforts, so it seemed logical that the run defense would greatly improve when they returned for the season opener.
The Dolphins, however, were able to find success on the ground early in the game. Reggie Bush averaged 4.9 yards per carry, and the Dolphins were able to effectively move the ball on the ground early in the game.
As the game progressed though, the Texans took a major lead and the Dolphins were forced to abandon the pass.
The run defense is certainly an important concern for the Texans, and Maurice Jones-Drew and the Jaguars should provide an excellent test.
Was it Trindon Holliday or Jacoby Jones returning kicks and punts for the Texans against the Dolphins?
After an electrifying preseason, Holliday's play in the season-opener was eerily reminiscent of Jones' performances for the Texans.
Holliday failed to get out of the 20-yard line on all three of his kickoff return attempts, and he also bobbled a kickoff in the end zone.
He did not show the same decisiveness and burst that he showed in the preseason, nor did he manage to make any plays with his incredible speed.
Hopefully it was just Week 1 jitters for the inexperienced returner, as he can be a major threat for the Texans if he can manage to duplicate his preseason in the regular season.
Holliday certainly has the ability to make impressive plays in the return game. His blazing 4.20 40-yard dash speed is absolutely incredible, and he runs with a toughness that is rare for a player who stands at 5'5".
Holliday has the capabilities to produce for the Texans, and now only time can tell if he will.
The offensive line's performance on Sunday was especially concerning, and their overall play in the season opener did nothing to alleviate the concerns that were brought up in the offseason.
Although the line definitely played well at certain points of the game, the overwhelming adjective that can be used to describe the line's performance is inconsistent.
The ground game was never able to actually get going, which made it a struggle for the entire Texans offense to get anything done. The Texans offense lives and dies by its rushing attack, and if the offensive line cannot block for the rush effectively, then the offense as a whole will experience major issues.
None of the Texans' linemen played well on Sunday; Duane Brown and Chris Myers even looked to be severely struggling at times.
Despite this, however, the offensive line will correct itself. The line is comprised of extremely talented athletes, and the problems will eventually be set straight. There will be growing pains after replacing 40 percent of the line, but the future success of the line should not be heavily doubted.
Be worried, though. Definitely be worried.
Like Trindon Holliday, Lestar Jean and Keshawn Martin both had amazing preseasons. Both looked like they could be major contributors to the Texans offense in the receiver position this season, and they gave Texan fans hope about the receiver depth behind Andre Johnson.
Jean's and Martin's performances on Sunday, however, were completely underwhelming. Jean had one reception for nine yards, though he came very close to hauling in a touchdown pass. The one target that Martin received all game was ultimately dropped by him, and he did not see much playing time afterwards.
While their performances might be discouraging after such encouraging preseasons, it should have been expected. It is rare that a receiver will contribute at all in his first season playing in the NFL, and it usually takes young receivers about three years to fully become integrated into an offense.
Out of the two receivers, it appears that Jean is much further along, so far. Since he is bigger, it is much tougher for opposing defensive backs to press him at the line of scrimmage. For Martin, however, his small frame allows defensive backs to easily press him at the line of scrimmage, and he must perfect his press-breakers if he wants to contribute significantly this offseason.
In a random and complete guess, I'm going to say that Jean will finish the year as a much greater contributor than Martin with 600 yards and three touchdowns, while I believe Martin will finish with around 300 yards and one or two touchdowns.