We have seen Boston Celtics guard Kemba Walker time and time again lay on the floor after taking a hit in a game, only to rise to his feet and keep playing. 

But tonight’s game against Denver was different. 

Walker was carted off the floor on a stretcher in the second quarter after a head-on collision with teammate Semi Ojeleye as Walker tried to corral a loose ball. 

Celtics officials later indicated that the three-time All-Star was diagnosed with concussion-like symptoms and will be transported to a nearby hospital for additional evaluation.

While no timetable for Walker’s return has been set, it’s likely he will miss a few games at a minimum. 

That means Boston’s “next-man-up” mantra will now be put to the ultimate test with their leading scorer sidelined with a yet-to-be-determined timetable for his return. 

For Boston, more pressure to carry the team will fall upon the shoulders of Jayson Tatum for sure. He has been the next-best scorer on the Celtics roster all season, so it’s only natural that Boston will lean more on him going forward.

After a so-so start to the season, Tatum has been playing at an all-star level with 20.9 points per game along with 7.4 rebounds and 2.4 assists while shooting 39.1 percent from 3-point range which speaks to how he’s capable of impacting the game on several levels.  

Jaylen Brown will also be looked upon to elevate his play in concert with Tatum. 

And like Tatum, he too has played well enough to be in the conversation to be an All-Star this season. 

He came into Friday’s game averaging 18.5 points, 7.2 rebounds and 2.2 assists while shooting 34.7 percent from 3-point range and a career-best 47.3 percent from the field. 

The duo has shown itself to be up to the challenge of playing without Walker, evident by both of them being among the only 10 players in the NBA averaging at least 18 points, seven rebounds, two assists and a steal this season. 

And of that 10-pack of players, they along with Dallas’ Luka Doncic, are the only ones on the list yet to be named an all-star. 

Marcus Smart’s growth into being a reliable two-way talent will have to be ratcheted up as well with Walker out. 

Depending on how long he’ll be out, we’re likely to see Brad Wanamaker’s role increased in addition to second-round pick Tremont Waters, signed to a two-way contract by the Celtics, get called up from the Maine Red Claws to provide added depth in the backcourt.

This season has had players in and out due to injury all season, with the most recent prior to Walker being Gordon Hayward (broken hand) who is likely back around Christmas time. 

But with Boston having so much depth at the wing to help fill the void by Hayward’s injury, Walker’s concussion is the first real adversity this Celtics team has faced this season. 

With concussions, there’s no black-and-white timetable for when a player is fit to return which differentiates it from a broken bone or an ankle sprain. 

The one thing we do know is that Danny Ainge built this team upon the premise of being deep enough to withstand the ups and downs of the season that includes injuries. 

Are they up to the challenge? 

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