Celtics-Pacers matchups to watch in the Eastern Conference Finals

BOSTON -- The Boston Celtics are heavy favorites heading into the Eastern Conference Finals against the Indiana Pacers, but the showdown is going to pose their toughest test of the postseason. 

The Pacers love to run run run on offense, and if that isn't enough they run some more. Tyrese Haliburton gets a dangerous fast-break going, and the Pacers have the big bodies in Myles Turner and Pascal Siakam to punish the rim in transition. Indiana was the second-best offensive team during the regular season (behind only the Celtics) and is the best offensive team this postseason with a 121.7 offensive rating, just ahead of Boston and its 118.9 offensive rating.

The biggest difference in this matchup comes on the other end though, as the Celtics possess a suffocating defense while the Pacers... do not. They did become a better defensive team after picking up Siakam at the trade deadline, but still finished the regular season with the 24th ranked defense. It hasn't been much better in the playoffs, with Indy ranked 13th with a 118.1 defensive rating. The Celtics are third at 106.1, after finishing the regular season second at 110.6.

The Pacers are obviously going to test that defense, but the Celtics have the talent, the long arms, and the scheme to slow it all down. And if they don't, they have the offensive firepower that should be able to keep pace in a track meet. 

Matchups aren't set in stone, especially when Boston's switch-heavy defense goes to work. But here's a look at some the key matchups to the Eastern Conference Finals.

Tyrese Haliburton vs. Boston's Backcourt

It all starts with Haliburton for Indiana, and he's coming off a huge series against the Knicks where he averaged 21.3 points per game off 53.8 percent shooting from the floor and 43.9 percent from three-point range. For Indy to have any chance this series, he's going to have to play at an other-worldly level. 

Jrue Holiday and Derrick White will be there to make sure that he doesn't. And when Haliburton is off, chances are the Pacers' offense is also off. He averaged 24 points in Indy's four wins over the Knicks, to just 11.3 points in their three losses.

He did have a monster game against the Celtics in the In-Season Tournament quarterfinals, logging a triple double and finishing with 26 points off 10-for-18 shooting. But he struggled from the floor in his other two full games against Boston -- he left their Jan. 8 meeting after just 13 minutes with an ankle injury, but was 3-for-5 before departing -- and was just 10-for-33 overall and 3-for-14 from deep.

Haliburton averaged just 15.8 points off 41 percent shooting against the C's, while averaging 20.1 points off 47.7 percent shooting overall during the regular season. Holiday and White made him work in the regular season, and that will continue over the next two weeks. Both have the length to limit his spot-up looks and if they get back on the break, they'll be able to muck up any open passing lanes.

Guarding Haliburton won't fall completely on Holiday and White. Holiday may find himself on Turner at times to defend Indy's pick-and-roll, and Jayson Tatum and Jalen Brown could potentially slip over to the Haliburton assignment in switches.

Haliburton can take over any game, but the Celtics have several capable defenders to make sure that he doesn't. 

Tatum and Brown vs. Siakam

Tatum usually found himself on Siakam during the forward's time in Toronto, but Brown may fight him for the matchup this round. Siakam is leading the charge for the Pacers at 21 points per game this postseason, and Brown is always looking to defending the opposing team's top scorer.

Siakam was on fire against the Knicks, shooting 52.8 percent from the field and 40 percent from three-point land. Nearly 60 percent of his playoff points have come in the paint, and over 82 percent of his points have been 2-pointers. Staying in front of Siakam is key for Boston, and thankfully Tatum and Brown are big enough and strong enough to do so. (While also being fully capable of dropping a 30 piece on the other end.)

Aaron Nesmith vs. The World

The former Celtic always has a chip on his shoulder when he plays Boston. The C's 2020 first-round pick struggled to crack the lineup in his two seasons in green, and was then traded to Indiana as part of the package for veteran Malcolm Brogdon two summers ago.

Nesmith has thrived with the Pacers as a high-energy defender and spot-up shooter, hitting 42 percent from deep during the regular season. That percentage has dropped to just 30.2 in the playoffs, but the Celtics still can't lose him on the arc this series.

There is always a fire in Nesmith when he sees the Celtics on the other side of the court. He'll likely find himself on Tatum, and his defensive exuberance will probably get to the Boston superstar from time to time. Tatum averaged 32.5 points per game against Indy in the regular season and should still feast this series, but watch out for Nesmith to play some real "playoff defense" against him this series.

Celtics vs. Crunch Time 

The Celtics were rarely tested during the regular season with more 20-point wins than close games, and that has carried over to the playoffs. Boston has played a grand total of 79 seconds of "clutch time" -- games within five points with five minutes left in the fourth quarter -- and that was when they let a double-digit lead slip away late against the Cavaliers in a Game 4 win. Nine of Boston's 10 playoff games have been decided by double digits.

The Pacers have played in four games decided by single digits this postseason, going 2-2 in those contests. That included two of their best wins over the Knicks. Boston and Indiana played three games that were decided by 10 points or less during the regular season, with the Pacers winning two of them. 

For the most part, Indiana played Boston tough during the regular season. It would obviously make life easier on the Celtics if they can recreate their 51-point victory over the Pacers every game, but at this stage of the playoffs, chances are they are going to find themselves in some clutch situations. 

If that's the case, the C's need to be ready to play their best and smartest basketball when the game is at its tightest. 

Kristaps Porzingis vs. Rust

The Celtics' big man isn't expected to play in the first two games of the series, but could potentially return when the series shifts to in Indiana. Or he's just looking for an excuse for a free trip to Indiana for the Indy 500. Saturday (the night of Game 3) would be roughly one month since Porzingis suffered the right soleus strain that knocked him out in the first round.

The Celtics should be able to beat the Pacers without Porzingis, so long as Al Horford sips from the Fountain of Youth again and his legs don't fall off after the first two games. And Boston shouldn't rush their stretch-big back until he is ready for all the rigors that go with an NBA playoff series, especially one against a cross-country team like the Pacers. Horford, Luke Kornet, and Xavier Tillman should be able to hold down the fort until Porzingis returns.

But getting him back into the flow of the game and knocking off some rust is also important. His absence shouldn't be too big of a factor early in the series, but getting Porzingis back later in the set would be huge for the Celtics and their potential road ahead.