JACKSONVILLE – This was well-deserved.

That's how Jaguars Head Coach Doug Marrone felt about the four-year contract extension signed over the weekend by linebacker Myles Jack – an extension that runs through 2023.

"I'm happy for Myles," Marrone said Monday morning as the Jaguars began preparing to play the defending AFC West Champion Kansas City Chiefs in the 2019 regular-season opener at TIAA Bank Field Sunday at 1 p.m. "I'm happy for all players who are able to go out and perform well and earn their contract."

Marrone on Monday discussed multiple Jaguars issues, including the week's Hurricane Dorian-forced schedule change, the health of weak-side linebacker Quincy Williams and game-planning for the Chiefs' potent offense. We'll discuss Williams and the Chiefs later in this Monday update.

Jack, a second-round selection in the 2016 NFL Draft, has played in all 48 games in three seasons. He started his career on the strong side, played middle in 2017 and moved into the full-time starting middle linebacker position last season.

"Here's a guy who can play all three linebacker positions," Marrone said. "I've always thought from the beginning that in all three of those positions he can excel and be one of the top performers at that position."

Jack was considered one of the top four or five prospects in the '16 draft before concerns over a knee issue caused him to slide in the draft. He also was one of the most versatile players in that draft, having played running back in addition to linebacker at UCLA. Marrone on Monday revealed that the Jaguars considered using him at running back when injuries weakened the position last season.

"You're talking about someone who's obviously an exceptional athlete," Marrone said. "I don't know if he's ever missed a practice, but he never has missed any games. He's never done anything of that nature except to be the best player he can be, then that player is rewarded – so yes, I think you are happy for that. You get rewarded by your performance and he has played very well for us.

"Now, we're looking forward to him taking his game to another level and making people around him better. He's excited for that."

Also Monday:

*Marrone said Williams is 100 percent entering the week after missing the preseason with a minor meniscus tear. Williams worked with the starters throughout organized team activities and early during training camp, with veteran Najee Goode working with the starters on the weak side in Williams' absence.

*Marrone lauded the Chiefs' offense, which is considered one of the NFL's most potent and which is led by quarterback/2018 NFL Most Valuable Player Patrick Mahomes. "It's a great challenge," Marrone said. "They have one of the top tight ends in the league (Travis Kelce), top receivers (Sammy Watkins and Tyreek Hill) – and different receivers … speed, route running, catching. You're talking about a quarterback who's an MVP. Our guys know they have to put a lot of work in and it's going to come down to being able to perform." Marrone added, "They have a lot of good football players; it's not just in one room – it's all over. There's a reason a lot of people have picked them to be in the Super Bowl. They have outstanding talent. That's the first thing that jumps out at you. They're a tough team to defend. They're a tough team to go against in all three phases and it's going to be a great challenge." …