The Boston Celtics suffered one of their worst losses of the season on Tuesday against the undermanned Washington Wizards, and it seemingly ruled them out for the one seed in the Eastern Conference in the blink of an eye. But after two dominant performances from Jayson Tatum, it seems like anything is a possibility for Boston throughout the remainder of the season.

The Celtics have been fairly inconsistent over the second half of the season, and Tatum has played a big role in those inconsistencies. But for a quick two game back-to-back stretch, Tatum finally looked like the superstar he was proving himself to be early on in the season. He dropped 40 points against the Milwaukee Bucks to lead Boston to a resounding 41-point victory over their top competition, and then scored another 39 the next night against the Utah Jazz.

Tatum has flipped a switch from out of nowhere, and has quickly shown why the Celtics are so dangerous heading into the playoffs. But at the same time, we have seen some ugly performances from Tatum along the way too, which has raised some red flags for the C's that cannot be overlooked because of two games. Boston's ceiling is incredibly high currently, but in order to reach that ceiling, they need Tatum playing at his best, which is why he's the Celtics biggest X factor entering the postseason.

Why Jayson Tatum is Celtics postseason X factor

Typically when you think of an X factor, it's a more under-the-radar player who could help a team go on a deep run if he lives up to expectations, or even exceeds them, but could also contribute to a disappointing run by failing to meet expectations. But looking at the Celtics, Tatum is clearly that player.

Prior to his recent two-game outburst, Tatum had been in a prolonged cold stretch. Since the All-Star break, he was still putting up strong numbers, but his efficiency from the floor was becoming increasingly worrisome (28.1 PPG, 9.9 RPG, 5.2 APG, 45.2 FG%, 29.4 3P%). The three-point shooting was particularly concerning, as that is a huge piece of Tatum's game.

After his two latest games, Tatum's numbers post All-Star break look far more normal (29.4 PPG, 9.8 RPG, 4.8 APG, 47.6 FG%, 34.2 3P%). It shouldn't be a surprise that Boston comfortably beat the Bucks and Jazz with Tatum playing at such a high level. Heck, his statlines from both games are nearly identical (40 PTS, 8 REB, 1 AST, 12-18 FGM vs. MIL, 39 PTS, 11 REB, 3 AST, 12-17 FGM vs. UTA).

Tatum isn't going to play at this ridiculously high-level every time he takes the court, but it's clear that when he's on his A-game, the Celtics are nearly unbeatable. He's finally found his stroke from behind the arc after shooting below 30 percent for much of the post-All-Star break stretch, and his improvements as a rebounder and passer have helped round out his game.

We have seen what the Celtics look like with an inefficient Tatum leading Boston for much of the second-half of the season, and the results weren't encouraging. For much of this recent stretch, Jaylen Brown has looked like the far more reliable player on offense for Boston, but the roles were reversed again against the Jazz when Brown struggled mightily for much of the game, only to get bailed out by Tatum.

Boston can win when Tatum isn't able to score, but their path to doing so is much more difficult than it is if he is leading their charge. Tatum has evolved to become capable of beating double teams and more attention from defenses thanks to his passing capabilities. Against Utah, the Jazz were doubling Tatum so high up the court that a simple pass was creating four-on-three situations for his teammates. That's the effect that a good Tatum game can have for the C's.

The Celtics have been built to make life for Tatum and Brown easier, and while they have the talent to overcome the occasional off game every now and then, their ceiling is clearly going to be reached when Tatum is playing his best basketball. For the last two games, Boston just showed how good they can be in a season where they have looked increasingly inconsistent as time has gone on.

Tatum cannot let this quick two-game stretch be a flash in the pan. Boston has been looking for momentum to carry over into the playoffs, and they may finally have found it. After an inconsistent second half of the season, Tatum has proven that the Celtics are still a force to be reckoned with. But whether or not they reach their ceiling is going to come down to whether or not Tatum can continue to play at a high-level moving forward, making him Boston's unlikely X-factor with the playoffs fast approaching.