From Celtics to Warriors, who are X-Factors in Eastern, Western Conference finals of NBA playoffs?

We know the stars will have a say in the outcomes of the NBA’s conference finals.

Boston’s Jayson Tatum, Golden State’s Steph Curry, Dallas’ Luka Doncic and Miami’s Jimmy Butler are the focal points.

But who are the non-stars – the X-factors – who will make a difference in the conference finals?

Grant Williams played the role perfectly in Boston’s Game 7 victory against Milwaukee on Sunday. Can he do it again at some point during the Celtics’ series against the Heat? Would Dallas be playing in its first conference finals since winning the NBA championship in 2011 without the timely baskets from Spencer Dinwiddie in the Mavericks rout of the top-seeded Phoenix Suns?

We take a look at two players from each team who need big performance to supplement the stars and help their team reach the NBA Finals.

Veteran Celtics forward Al Horford (42) battled Bucks forward Giannis Antetokounmpo (34) throughout the seven-game Eastern Conference semifinal series.

Boston Celtics

Grant Williams

Williams scored a game-high 27 points and made 7-for-18 3-pointers in the Celtics’ series-clinching victory. Does he need to replicate that? No. But Williams is a player who has developed into a defender who can also shoot 3s, and the Celtics need his offense, especially at times when Miami will make scoring difficult for Jayson Tatum and Jaylen Brown. Williams will also have several opportunities to make an impact defensively.

Al Horford

Horford rejuvenated his savvy old-man game with the Celtics this season and the playoffs in particular. He has had different matchups in the first two rounds and will get another challenge against Miami's Bam Adebayo. Horford’s ability to defend and stretch the floor increases Boston’s versatility.

Miami Heat

Max Strus

This is how far Strus has come in a year. Last season, he appeared in just two playoff games for a total of six minutes. Now, Strus is in the starting lineup, playing nearly 30 minutes per game, averaging double figures in points (12.5) and shooting 35.1% on 3-pointers. With Duncan Robinson in a reduced role (for now), the Heat need Strus’ shooting.

P.J. Tucker

Tucker was vital to Milwaukee’s championship run last season, and the Heat want him to play a similar role. He is a physical defender, rebounder and overall irritant who likes to get under the skin of opponents. Tucker provides just enough offense with his 3-point shooting in the corners and offensive rebounding to make teams pay attention to him.

Golden State Warriors

Draymond Green

Green seemed almost unwilling to shoot at times against the Grizzlies. While scoring will never be Green’s top priority for the Warriors, they will need him to be much more aggressive offensively against Dallas. He must attack when the Mavericks give him the opportunity and not allow them to load up on the perimeter to stop Golden State’s shooters.

Otto Porter Jr.

The Warriors are hopeful Porter is ready for Game 1 after sustaining a foot injury and missing the clincher against the Grizzlies. If he can go, Porter’s presence will be key on the defensive end for Golden State, where at 6-8, he gives the Warriors another big wing player to match up with the Mavericks’ abundance of size on the perimeter.

Spencer Dinwiddie (26) celebrates his three-pointer as Suns forward Torrey Craig (0) looks away during Dallas' stunning Game 7 win.

Dallas Mavericks

Spencer Dinwiddie

After being cast out in Washington, Dinwiddie settled into his role of lead scorer off the Dallas bench. The Mavericks’ offense is formidable when he is a reliable third option while Luka Doncic and Jalen Brunson initiate most of the offense. Dinwiddie’s 30 points on 11-of-15 shooting in the closeout win over the Suns is the best version of that.

Maxi Kleber

Kleber didn’t have a great series against Phoenix, but the threat of his shooting at 6-10 allows Dallas to stretch opposing bigs away from the paint and out to the 3-point line. The Mavericks’ long-range shooting can feel like an avalanche when they’re hitting, and Kleber can be a major part of that while opening more space inside for Doncic and Brunson to get to the basket.