COSTA MESA, Calif. -- Los Angeles Chargers offensive coordinator Ken Whisenhunt had trouble finding the words as to why backup quarterback Cardale Jones experienced a breakthrough on the field in his third season with the team.

"I wish I knew the answer to that, because if that was the case, I would have liked to have seen that two years ago," Whisenhunt said. "Not anything against Cardale -- I'm extremely excited about the way that he's performed in our camp. Maybe it's just the process of growing up a little bit.

"He came out young. And maybe it's being in the same system for a couple of years. It has been different [this year], and that's a credit to him. He's worked hard. You could see it early in the spring. It's nice to see him perform the way that he has on the field. He's done a really nice job."

Jones was a fourth-round selection by the Buffalo Bills in 2016 after entering the draft early out of Ohio State. The Chargers traded a seventh-round selection to Buffalo before training camp in 2017 because of Jones' untapped potential and relationship with coach Anthony Lynn.

Jones recorded an 11-0 record as a starter for the Buckeyes, leading Ohio State to a national championship in 2014 after starting the season as the third-string quarterback. He beat Wisconsin in the Big Ten championship game and Alabama and Oregon in the College Football Playoff after replacing an injured J.T. Barrett late in the season.

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That run, combined with his 6-foot-5, 250-pound size and strong arm, made Jones a bit of a folk hero and an intriguing draft prospect. The Chargers did their homework on Jones prior to the 2016 draft, with quarterbacks coach Shane Steichen traveling to Ohio State to hold a private workout.

However, in his third season with the Chargers, the 26-year-old Jones is at a crossroads, fighting with rookie Easton Stick to hang on to a roster spot while suitors in the XFL loom.

Los Angeles Wildcats offensive coordinator Norm Chow and Tampa Bay Vipers coach Marc Trestman recently attended Chargers training camp. The XFL has stated a willingness to pay quarterbacks decent money to make the new league more competitive and appealing to fans.

The XFL already signed former NFL quarterback Landry Jones, and league commissioner Oliver Luck has expressed a desire to sign seven more leading signal-callers for the rest of the franchises.

"There are very good young quarterbacks available," Luck said. "We can do a more selective job at the top of our roster and get better players."

During his first two years playing in preseason games for the Chargers, Jones exhibited up-and-down play, struggling to learn the offense and his role in it. Jones was 49-of-86 (57%) for 454 yards, with one touchdown pass, three interceptions and two lost fumbles. Jones was sacked 12 times, posting a 60.9 passer rating.

However, Jones has shown improvement in three preseason games this year, completing 18 of 25 passes (72%) for 208 yards, with a touchdown and no turnovers. Jones has been sacked just twice, posting a 110.1 passer rating.

So what's been the difference?

"It just comes from being in a system for consecutive years and being around a guy like Philip [Rivers]," Jones said. "The experience that we have in the room and the relationships we have in the room with guys like coach Whiz [Whisenhunt] and coach Shane [Steichen], things like that.

"It's seeing how Phil goes about his business and just kind of taking some of the things that he does in his normal routine and just trying to incorporate those things into my everyday life."

Added Lynn: "He understands that if you want to be good at this league and take your game to the next level, you definitely have to outwork and work as hard as anyone with no sympathy. Not saying that he wasn't a hard worker, but the things that I see now, all the extra effort that he’s doing, I didn't see before."

Specifically, Jones showed his development in a play against the New Orleans Saints last week, hanging in the pocket and giving receiver Andre Patton extra time to shake loose on this 24-yard touchdown pass.

Patton said he and Jones had been working against that specific scheme in the joint practices against the Saints leading up to the game, and finally got the look defensively they were expecting.

"We have definitely built a relationship the last three years," Patton said about Jones. "We were both on the practice squad. Before the home games we would always work out and run routes. You can see in practice that our chemistry is there."

But is this breakthrough too little, too late? Jones faces a potential numbers crunch in his attempt to make the 53-man roster.

Jones spent his first season with the Chargers as the No. 3 quarterback on the active roster behind Rivers and Kellen Clemens. He spent last season on the practice squad as the No. 3 quarterback behind Rivers and Geno Smith.

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This season, Jones again is trying to earn a spot on the active roster behind Rivers and Tyrod Taylor, but he is in a training camp battle with Stick, a fifth-round pick out of North Dakota State. It's a competition that likely will come down to the final preseason game on Thursday at the San Francisco 49ers. Stick has shown flashes with both his arm and legs this preseason, but Jones is right in the mix with him.

"You have got to sustain it," Whisenhunt said, when asked about expectations for Jones. "A lot of times in this league that it's a flash -- a flash-in-the-pan type of thing. You want to see sustained success or sustained ability to handle what's coming at you. ... You have to measure it in total. It can't just be one game or one half. It counts, what he has done in practice, too. Once again, I'll say that he has done a nice job."

Jones said he is not concerned about the decision-making process on whether he stays or goes.

"That's totally up to the coaches to decide," Jones said. "My job is to take advantage of each and every one of my opportunities and control what I can control."