How will Kemba Walker respond in biggest game of his career?

Thirteen months ago, a beaming Kemba Walker sat at a podium inside the Auerbach Center with the Celtics’ 17 championship banners hanging behind him, and was asked why he chose to sign with Boston.

“You see all the banners upstairs and in the arena. It’s a winning organization and I want to win,” said Walker. “That’s what I’m about. Throughout my basketball career, as a pro, I haven’t won consistently, and I just want to get a taste of that and I thought this would be the best place for me to do that.”

The opportunity that Walker so desperately craved in that moment is before him now. Friday night’s Game 7 of an already epic Eastern Conference semifinal series against the Toronto Raptors will be the biggest game of Walker’s pro career. It’s one that could shuffle the Celtics a step closer to competing for another banner, or leave the team wondering what could have been.

Coming off one of his toughest shooting performances in green, a Walker rebound is vital to Boston vanquishing the defending champions. He doesn’t need to be otherworldly, and don’t judge his line solely by scoring output, but the Celtics could very well need some of his fourth-quarter Cardiac Kemba magic if they are to punch their ticket to play the Heat in the East finals.

Blakely: Tatum needs to be better version of himself in Game 7

It’s been four years since Walker played in the only other Game 7 of  his career. He labored through 3-of-16 shooting that night in a first-round series against Miami, scoring only 9 points as the Heat throttled Charlotte by 33 points.

What’s different now is that Walker has help around him. He doesn’t need to be superman to carry his team during a must-win game. But he most certainly has to be better than what we saw at times during Game 6.

Stifled by a box-and-1 early, then unable to find a rhythm — or a whistle —  late, Walker finished with only 5 points on 2-of-11 shooting over 51 minutes, 41 seconds of floor time. He had three turnovers and Boston’s offensive rating was a team-worst 105 when he was on the court.

“I got to find a way to help my teammates more,” said Walker. “I got to be better for my teammates.”

The NBA’s tracking data had Fred VanVleet holding Walker scoreless over nearly 10 minutes of matchup time and 35.1 partial possessions. Walker missed all five shots against VanVleet while getting blocked once and turning the ball over once.

VanVleet was a thorn in Walker’s side for most of the night. On one of the game’s first possessions as the Raptors displayed their box-and-1, VanVleet pickpocketed Walker coming off a screen and created points in transition.

Later, in the final seconds of regulation, Walker accelerated past VanVleet but Toronto’s guard contested the layup from behind — somehow avoided a whistle despite a bit of contact — and sent the game to overtime.

Rubbing salt in the wounds, the NBA announced in its Last 2 Minute report Thursday that OG Anunoby should have been whistled for a foul on that Walker drive after he “makes contact to Walker’s arm during his shooting motion that affects his driving shot attempt.”

Walker, so solid in crunch time this postseason, went on to miss a go-ahead 3-point attempt in the final minute of the first overtime and the Raptors routinely forced him to be a facilitator in the extra sessions.

What happens next? That Game 7 against Miami and Game 6 against Toronto were the quietest nights on Walker’s brief playoff resume. He had a poor shooting night in Game 5 of that same Heat series in 2016 (4-18 FG, 14 points) and bounced back with 37 points on 14-of-30 shooting to force that Game 7.

One thing is certain: Walker never quite lingers on a bad shooting performance. He is the king of “the next shot is going to fall.” Confidence will not be an issue.

Again, Walker doesn’t need a big scoring output for Boston to win this game. If Toronto swarms him again and clogs up paths to the basket, the right play will be to give up the ball. Jayson Tatum and Jaylen Brown should feel disrespected if the Raptors elect to focus their energies solely on slowing Walker.

Here’s Boston’s opening possession from the start of the game and how the box-and-1 disrupted their offense:

Celtics turn the ball over in first possession of Game 6

Walker’s initial attempt to drive is thwarted with VanVleet hounding him and help coming from within the box. Walker gives the ball up and Jaylen Brown nearly breaks the zone but turns it over trying to feed across to an open Tatum.

If the Raptors try to take away Walker drives, the Celtics can adjust by trying to get him more catch-and-shoot opportunities. Only three of his attempts in Game 6 were catch-and-shoot — and it was a relocation 3 that showed how Walker can give the ball up and get a good shot back.

Kemba Walker sinks the relocate three vs the Raptors

Walker admitted that he simply missed some quality looks, too. Ten of his 11 shots were deemed open (4-6 feet of space) or wide open (6+ feet of space). He made only two of those shots, however, including just one of four 3-pointers. Walker also did not attempt a single free throw in the game because the Raptors took away opportunities to attack. That might make transition chances even more important for Walker.

Celtics coach Brad Stevens didn’t seem overly concerned by Walker’s struggles.

“In the first half, that’s not really fair to Kemba because they’re in a box-and-1 on him, playing on top of him. And we are getting great shots against it, throughout the entire first quarter,” said Stevens. “At that point in time, his job is to either be a spacer or a cutter or a screener, and watch everybody else score. Then, when they get out of it, then he gets better opportunities.

“So that’s not on Kemba, anything about the three attempts in the first half or anything like that, it was how they were guarding him. They took him away, great sign of respect.”

Now it’s a chess match to see if the Celtics tweak anything to exploit any additional attention on Walker, or if the Raptors alter their approach as well. More importantly, what kind of motivation does Walker play with after his quiet night?

Walker came to Boston to compete for a title. Friday is a chance to move closer to what has evaded him throughout his NBA career.