GLENDALE, Ariz. -- The Arizona Cardinals opened their 2021 NFL training camp Tuesday at State Farm Stadium. Here's a closer look at a few storylines:

Is coach Kliff Kingsbury on the hot seat, what does he need to do to keep his job?

In short, yes, Kingsbury is on the hot seat. Yes, the Cardinals have improved every season he's been the head coach -- from five wins in 2019 to eight wins in 2020. But the bar was set low when he was hired after Arizona's 3-13 season in 2018. The reason he's on the hot seat is because of how close Arizona was to getting to the playoffs last season before nosediving during the second half of the schedule. If Arizona misses the playoffs this season for any reason other massive injuries, it's conceivable Kingsbury will be fired. He has a star quarterback in Kyler Murray, a star receiver in DeAndre Hopkins, a great No. 2 receiver in A.J. Green, a solid offensive line with a star center in Rodney Hudson and a star left tackle in D.J. Humphries, and a reliable backfield with James Conner and Chase Edmonds. What more can an offensive-minded head coach want?

What is the biggest thing the Cardinals have to fix from last season to become a playoff team?

They can't rely completely on Murray. The Cardinals need to be able to pivot when things go wrong and lean on other players. As Murray has said, his legs are a "luxury." So, if he gets injured this season and part of his game is taken away, Kingsbury must figure out a way to make up for that void with other players, something that did not happen last season. If Hopkins is double teamed, Arizona must find ways to move the sticks, get yards and score touchdowns with Green. For the Cardinals to make the postseason, they must overcome adversity.

How effective will J.J. Watt be in the Cardinals' defense?

Defensive coordinator Vance Joseph's scheme will give Watt -- signed as a free agent this offseason -- opportunities to blitz and rush the passer. That's the way Watt prefers to play. Plus, Watt will likely have Chandler Jones on the opposite side, which would open up one-on-one opportunities. Sources told ESPN's Jeremy Fowler, however, that Jones requested a trade this offseason. Jones is coming off a biceps injury that ended his 2020 season in Week 5 after recording 19 sacks in 2019. Watt has been posting his workouts on social media and looks like he's in some of the best shape of his career. If that translates to the field, then his production will force teams to decide who to double team: him or Jones. That could leave Watt open for straight lines to the quarterback.

Is this the year the Cardinals' offense -- with Kyler Murray, DeAndre Hopkins and A.J. Green -- finally takes off?

It should be. The Cardinals have all the offensive pieces they need to put Kingsbury's offense into full effect. Not only is Murray in his third season, which means he has the necessary experience to make the type of leaps expected out of elite quarterbacks, he has as close to a full offseason as he can get with his new weapons to jell before they get on the field, unlike last season. Those weapons include two of the best receivers in football in Hopkins and Green. The amount of time the trio spends together will be immeasurable on Sundays. The pieces to Kingsbury's offensive puzzle are there. It's just a matter of whether he can put them together to make the scheme sing.