The Miami Dolphins lost a must-win game in Week 17 against the Tennessee Titans, 34-3. It was the worst that they looked all season as they failed to show up when it mattered most.

This was probably the most disappointing loss for the Dolphins in a long time as they are now in a very tough spot to make the playoffs. Miami was able to control their own destiny, but unfortunately, failed to take care of business against the Titans. If they would have just won this game and then beat the New England Patriots in Week 18, they would have had a playoff spot secured. Now they are going to need some luck to go their way and they're also going to need to beat a tough Patriots team. Things aren't looking as planned for the Dolphins, but they still do have an outside shot and they're just going to need a few things to happen.

Let's take a look at four key takeaways from the Dolphins' Week 17 loss to the Tennessee Titans.

*Watch NFL games LIVE with fuboTV (Click for free trial)*

Dolphins Week 17 Takeaways

4. Tua looked his worst when he needed to be his best

Tua has actually looked pretty good for the past few games when he has been somewhat healthy. Unfortunately on Sunday, he did not play anywhere near to his capability and that saw the Dolphins' offense being arguably the worst that it has ever been.

This was a game that he really needed to show the world that he can be a very good quarterback in this league and he did not do so. He went 18-38 for 205 yards and also threw an interception. In his fairness, there was some tough weather out there on Sunday and that was certainly part of the problem of his passing game. At the end of the day, a good quarterback is always going to find a way to get the job done and he did not do that for the Dolphins on Sunday.

3. Defense looked like it did early in the season

The Dolphins' defense for the past seven games prior to this was the best in all of the NFL in least points allowed and they also had the most sacks. Clearly, on Sunday, they did not play the same way that they were during their six-game winning streak on the defensive side of the ball, but there can't really be much blame for them when the offense failed to do anything. It is unclear what type of defensive schemes the Dolphins were running that they were not running the past seven weeks. It looked like the defense that they were playing in the beginning of the year before they decided to go back to the defense that saw them be one of the best a season ago.

2. Failed to win a big game once again

This has been the issue with the Dolphins for the past few years and unfortunately, it didn't change on Sunday.

There are plenty of things that can be put to blame for this, and certainly one of them this season is having a young team and also having a coach who hasn't necessarily played in many big games. Their offense did not look as good as it could have been and their defense certainly did not play as they usually do.

If the Dolphins are going to want to have any success in the next few years, they're going to either need to take care of business early on in the season against worst teams, or take care of business in the back end of the year when their backs are up against the wall and they are in must-win games.

1. Playoff chances are still alive

The Dolphins have definitely made it much tougher on themselves than they would have if they could have just taken care of business this game. The reality of the situation is now they are looking from the outside-in to the playoff picture. Just because they lost this game however doesn't mean that they cannot make the playoffs. It's going to take a lot of luck and it's going to need a Miami Dolphins win next week, but a possibility is a possibility and the Dolphins certainly have that.

The losses to the Atlanta Falcons and the Jacksonville Jaguars are certainly going to come back to haunt this team if they do not make the playoffs. They did not play as well as they needed to in the beginning of the season and they are starting to see what comes with disappointing play throughout the year.

The playoffs are still alive, but a miracle is going to need to happen so the Dolphins better start hoping that some teams can pull out wins against other teams that they need to lose.