Celtics still have something to prove as they hit a tough stretch to start March

BOSTON -- The Celtics continue to roll through their competition, winning nine straight. They remain the best team in the NBA by a large margin as the calendar flips to March.

No one is really slowing down Jayson Tatum or Jaylen Brown at the moment. Or Kristaps Porzingis and, in crunch time, Derrick White. Even Joe Mazzulla is in the good graces of fans and the media alike, which is a rare occurrence with the lightning rod of a head coach. 

But as the saying goes, March comes in like a lion, and that will be the case of the Celtics. They'll be matching up with playoff teams in each of their next five games, and in six of their next eight. 

That run starts Friday night, when the C's put their five-game home winning streak on the line against the 34-25 Dallas Mavericks. The Mavs have won eight of their last 10, including a 136-125 win over the Raptors on Wednesday night. 

Luka Doncic loves to put up big numbers against the Celtics, and he comes to Boston fresh off a triple-double Wednesday, when he celebrated his 25th birthday by lighting up the Raptors for 30 points, 16 assists and 11 rebounds. It was his ninth straight game with at least 25 points, a stretch that has seen Doncic hit the 40-point mark twice.  

When the Celtics are done with Luka, Kyrie Irving and the Mavs on Friday, they'll then host Golden State on Sunday. Not only do the Warriors remain Boston's boogeyman, earning an overtime win over the C's in San Fran in November, but they've also won 10 of their last 12. Plus, it's always dangerous to face Steph Curry on national television.

After those two on the TD Garden floor, the C's hit the road against the Cavaliers (38-20, tied for second in the East) next Tuesday. The Cavs have won 20 of their last 25 and are the second-hottest team in the NBA (behind the C's, of course.) Boston will then go for some revenge against the defending champion Nuggets (41-19, third in the West) in Denver on Thursday night. Denver has won five straight and seven of its last 10.

The tough five-game stretch ends with a meeting with the 35-24 Suns in Phoenix next Saturday night, but the road trip continues with games against the Blazers and the Jazz.  And when the C's get back to Boston, they'll face the Suns again on Thursday, March 14. 

It's going to be quite the stretch -- and test -- for the best team in the NBA.

The Celtics haven't had any issues with difficult stretches so far this season. They've yet to lose more than two straight, and they haven't lost back-to-back games since early November. They're also solid against current playoff teams, touting a 27-11 record against the top 10 in each conference (themselves excluded, of course). If you take out the play-in teams, which currently includes the Mavs and the Warriors in the West, the Celtics are 15-7 against the six best teams in both conferences. 

But each of their last three losses have come against two playoff teams and one play-in team (the Nuggets, Clippers, and Lakers) and all three of those came on the Garden floor. A strong stretch right now (especially in their rematch against the Nuggets) would go a long way to ease any concerns from those three defeats.

While the goal is obviously to bring home a title, the Celtics have set the bar extremely high for the rest of the regular season. The rest of the league has given very little resistance as Boston has torn through the NBA to an incredible 46-12 record and a league-best 10.6 net rating, but the pressure will be ramping up as the postseason inches closer.

A tougher schedule against teams that are also on a roll should just give these Celtics another level of motivation to keep up their dominant ways. While the team has won nine straight, Celtics doubters will point to their last three losses as ways to question their championship gusto. 

The Celtics can continue to make those doubters look silly by racking up more quality wins against playoff teams over the next week.