Time to finally find out what these Celtics are made of

All season long, these Celtics have toyed with our emotions.

One day, they’re unbeatable juggernauts and the clear championship favorites. The next, they make the Magic look like the Monstars.

Navigating a championship-or-bust season isn’t necessarily easy, but they’ve made it a lot more difficult than it has to be with their maddening inconsistency. All along, we’ve told ourselves, "they’ll turn it on when it matters most.” Part of that is a coping mechanism and part of it is justified.

They can turn it on when they have to, but will they? Well, we’re about to (finally) find out.

After one of the most embarrassing and head-scratching losses of the Jayson Tatum and Jaylen Brown era – now down 3-2 to the 76ers and one loss away from a potentially fascinating, premature offseason – the Celtics get the chance to show everyone what they have deep inside.

“It happened. It’s unfortunate, right?” Tatum said. “We wish we could change it, but that’s not how life works. We just have to get ready for Thursday.”

There’s no more waiting for the right moment. No more hoping their frustrating tendencies will magically disappear. No more expecting someone else to lead the charge. Each player has to take it upon himself to ensure that a woeful performance like Tuesday’s never happens again.

“It’s a true dogfight,” Marcus Smart said. “Scratching, clawing, biting, blood, everything. If you’re not willing to pretty much get dirty, if you’re not willing to bleed, if you’re not willing to break something, if you’re not willing to tear something, going hard, then you shouldn’t be on that court.”

I think we can all agree that the Sixers have earned a collective hat tip so far this series. They’re playing the game on their terms and dictating the pace. They’ve had the best player and haven’t let the Celtics’ depth wear them down as much as it probably should.

Philly deserves to be up 3-2 right now, and if it wins this series, I like its chances to go all the way.

Now having said that, the effort the Celtics have put forth has been uninspiring at best and franchise-altering at worst. Game 1 was a reality check. Game 2 was a success. Game 3 was impressive. Game 4 was too little, too late. Game 5 was straight up brutal.

I went into Game 5 expecting the Celtics to play their best when it mattered most and outlast the 76ers in a back-and-forth battle. Yeah, that didn’t quite happen.

“I think we just didn’t have it today,” Tatum said. “Throughout the playoffs, we’ve played really well, even though we’ve lost a few games. Today was just kind of like a tough day for us.”

Great teams have off days every once in a while, but championship teams don't have off days when they need to be at their best.

So, what’s next? Well, we finally get to see what kind of fight this team truly has. We know Smart will be ready. Will Tatum make a shot in the first quarter? Will Brown keep it going the whole game? Will Robert Williams look for his offense? Will Derrick White be more aggressive? Will Malcolm Brogdon get in James Harden’s face? Will Al Horford make a corner 3? Will anyone stop that darn MVP?

If the Celtics don’t come out absolutely flying – and set the tone early like the Sixers did in Game 5 – they don’t deserve to win it all. If they do, and they survive in Game 6 and take Game 7 — this will benefit them immensely in the long run.

Remember, against the then-defending champion Bucks last year, the Celtics overcame a 3-2 deficit in the Eastern Conference semifinals and won the series in seven games. It can be done.

Does this team have that same mental fortitude and willpower? We’re about to find out.

“Last year’s over with,” Brown said. “This year, we have to come out and be better than we were tonight, or we’ll have a different ending.”