BOCA RATON, Fla. — Mark Sanchez has a lot to prove to Gary Kubiak and the Denver Broncos.

The Super Bowl champions aren’t just going to hand Sanchez the starting job, even if he’s the most accomplished quarterback currently on their roster. The Broncos acquired Sanchez from Philadelphia after Peyton Manning retired and Brock Osweiler signed with Houston as a free agent.

“I think he is going to have to make us comfortable,” Kubiak said Tuesday at the NFL owners’ meetings. “He’s going to have to come in and do his job. Mark hasn’t asked for anything. He just wants an opportunity to compete. We can give him a tremendous opportunity to do that right now.”

Sanchez was the fifth overall pick in the 2009 draft and led the New York Jets to the AFC championship game his first two seasons. He eventually lost his job in New York and spent the past two years as a backup with the Eagles, going 4-6 in 10 starts.

“He’s been on some big stages and he’s got an excellent chance to get back on one again,” Kubiak said. “I think that’s what he’s excited about and I think that’s also something that intrigues us about how willing he is to get going here and be a part of our football team.”

Trevor Siemian is the only other quarterback on the Broncos roster and he took a knee on his only snap as a rookie in 2015. Denver will likely draft another quarterback next month and could add another veteran either through free agency or another trade.

MORE REPLAYS: John Harbaugh doesn’t hide his feelings about ramping up replay.

The Ravens coach gave an impassioned monologue about it on Tuesday, stressing player safety.

“Safety should be in replay,” Harbaugh said. “The fact that safety is not in replay right now just makes absolutely no sense whatsoever.

“If we’re talking about a full-speed shot and the official’s got to decide, right in the moment, if he got hit in the head or not, he doesn’t want to make a mistake, he doesn’t want to flag that 15 yards because that’s going to alter the game. He may not throw that flag.

“But if he knows he’s protected by replay and he thinks there was helmet (or) neck area contact, he’ll throw the flag. And then if you see it on the replay, ‘Oh, he didn’t get it on the head,’ we’ll throw the red flag and we’ll get it right. To me that protects the player even more.”

Several teams have proposed expanding use of replay to cover virtually everything, and allowing more challenges — or making all plays challengeable. Harbaugh claimed the outcome of five games in 2015 was decided by “non-reviewable calls.

“The fans don’t understand that,” he added. “They don’t want to look at that all week and see that … the official made a mistake that everybody can see — the fans saw it in real time — that the league (subsequently) said, ‘It’s not reviewable. We can’t fix that.’ What do you mean we can’t fix it? We can’t fix it because we decide not to be able to fix it. We can fix it. Just fix it, make it reviewable.”

CHINA GAME: If the NFL is serious about playing a regular-season game as early as 2018 in the world’s most populous country, it has a lot of work to do.

Starting with where to stage the match.

“Whether the NFL regular-season game in China will be a success largely depends on which city it chooses,” says Jin Xin, manager of Great Stone Gridiron, an American football school in Beijing. “It’d better to be in one of the first-tier cities such as Beijing, Shanghai or Guangzhou, where there are more fanatics for this sport and some superb amateur American football teams are already flourishing.”

Jin remains skeptical about the prospect of such a game being embraced in his country. While the NBA has made inroads in China, the sporting culture there is more attuned to Olympic sports.

“Otherwise, people generally don’t know much about this sport,” Jin adds. “Even though I have no doubt the NFL has excellent brand image, I’m still conservative in predicting the commercial success of the game in China in two years. It may have more viewers online, but I don’t think there will be a good attendance rate in the stadium.”

The league said Monday it is conducting research into the feasibility of playing a game in China.

A NICE DILEMMA: Mike Tomlin laughed heartily when asked about finding work for running back DeAngelo Williams next season with backfield star Le’Veon Bell returning from the injured list.

“That’s a good problem to have,” Tomlin said. “We have two really capable running backs, so we will not turn it into an issue. I have been in the situation where I haven’t had any, and I prefer to have both of them.”

Bell, an All-Pro in 2014, played in only six games last season before tearing up his right knee. He was averaging 92.7 yards a game when he was injured.

The veteran Williams, Carolina’s career rushing leader before joining Pittsburgh a year ago, stepped in admirably. He started the final 10 games, rushed for 907 yards and scored 11 touchdowns. He turns 33 next month, but showed he has plenty of skill left.

AP Pro Football Writers Barry Wilner and Rob Maaddi, and AP researcher Dong Tongjian in Beijing contributed to this story.

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