Jay Williams examines how LeBron James missing time with an injury could provide other Lakers with an opportunity to step up. (1:27)

Editor's note: LeBron James is listed as day-to-day after an MRI confirmed a strained left groin.

OAKLAND, Calif. -- The Los Angeles Lakers got a win on Christmas, and they also got a test: Can they keep heading in the right direction if LeBron James' strained groin muscle causes him to miss significant time?

"This is uncharted territory, obviously, with this group," Lakers coach Luke Walton said after his team's impressive 127-101 win over the Golden State Warriors. "But this is what we've been talking about. This is what we try to plan for -- not that [James] gets hurt, but being able to play and win and compete when he's not on the floor.

"That's a process, and our team is much better than at the start of the season. So, it'll get a lot more challenging for us if he misses some real time, but I'm also very confident in our group that they'll continue to step up and battle."

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"The good thing is the muscle is intact," James told ESPN after Tuesday night's victory.

He was generally in good spirits and wouldn't rule out playing Thursday at the Sacramento Kings, though the results of an MRI on Wednesday will determine just how plausible that will be. If James is out of the lineup, the Lakers suddenly will face the challenge that the Cleveland Cavaliers could never seem to figure out over the past four seasons: winning without him.

The Cavs were a miserable 4-23 in games that James missed either for rest or injury over that span -- 3-10 in 2014-15, 1-5 in 2015-16 and 0-8 in 2016-17. The only reason it didn't hurt Cleveland again last season was because James played in all 82 games.

A rough patch with James out could derail the work the Lakers did through their 20-14 start to this season, giving the team the No. 4 spot in the ultracompetitive Western Conference standings.

With the Houston Rockets surging (7-1 over their past eight games), a couple of bad weeks -- say a 1-7 stretch -- could quickly drop L.A. out of the playoff picture, at least temporarily.

"This is what we try to plan for -- not that [LeBron James] gets hurt, but being able to play and win and compete when he's not on the floor," Lakers coach Luke Walton said. Thearon W. Henderson/Getty Images

The Lakers have had the misfortune of suspensions to Rajon Rondo and Brandon Ingram as well as lengthy injuries suffered by Rondo, Ingram and JaVale McGee this season already, and they kept things going. Of course, none of those players matches James' contributions. None has so much of the offense run through him. None can dictate the team's effort game to game like James. But some experience in dealing with adversity is better than none.

"We've been missing guys all year," guard Lonzo Ball said. "Obviously, LeBron's a really big part of this team. ... We have a lot of good guys on this team. We've been confident all year. It's not just one player on this team; we have a good team.

"Obviously, we want him back as fast as possible, but however long he misses, if he does miss, we've got to do our thing."

They all did their things against the Warriors, as six players other than James (17 points) scored in double digits, and Kentavious Caldwell-Pope almost made it seven with his nine points.

It's not hyperbole to call Tuesday's contest the biggest game that players such as Ball, Ingram, Kyle Kuzma, Ivica Zubac and Josh Hart have ever competed in: a marquee matchup on Christmas Day against the back-to-back champs stacked with All-Stars. And not only did they win without James available for most of the second half, they pounded the Warriors on their home court, pushing the lead out to 31 points after Golden State had briefly cut it down to two points with James out.

Part of the plan in James coming to L.A. was always about finding a graceful way to balance his inevitable decline while still staying competitive thanks to younger teammates on the rise. Nobody thought that balance would have to be struck quite so soon, but here we are. Or here we might be, depending on that MRI result. The training wheels could be coming off.

"I mean, it's not like we're panicking 'cause he's gone," Kuzma said. "We're pros too. We're great players, on our way to trying to be great players. It's all about that next-up mentality and having a will to win."