Nikola Mirotic of the Chicago Bulls (Photo by Jonathan Daniel/Getty Images)

Chicago is heading into the second round with the healthiest roster it has had in years, but they’re running into the same roadblock that had has bested them in three of the last five seasons: a LeBron James-led opponent. Chicago Coach Tom Thibodeau, however, has rookie forward Nikola Mirotic this time around.

Despite averaging 16.2 minutes through the first month of the season, the 6-foot-10 Serbian’s tremendous second-half of the regular season vaulted him into the rookie of the year conversation, finishing second to Andrew Wiggins of the Minnesota Timberwolves. As ESPN’s Micah Adams noted, his win shares per 48 minutes figure—a metric calculated by that attempts to assess how much a player contributes wins to a team—was historically high: Only David Robinson, Michael Jordan, Shaquille O’Neal, Tim Duncan, and Chris Paul posted a better WS/48 figure than Mirotic in their rookie seasons, and Niko’s figure was higher than 25 of the last 30 players who won rookie of the year.

This postseason, however, Mirotic’s stat line has been mild at best: 4.6 points, three rebounds, 1.6 assists, 0.4 free throw attempts with a 36.7 effective field goal percentage. He isn’t shooting particularly well from anywhere on the court outside of the restricted area, but he also is hardly shooting at all.

Nikola Mirotic

Much could be from the injuries he suffered in the Game 2 victory over the Milwaukee Bucks. Mirotic was involved in a number of skirmishes with Zaza Pachulia and left the game—his most productive of the postseason—with strained quadriceps and a swollen left knee. He missed the following game and has averaged just 15.3 minutes per contest since.

Despite playing fewer minutes in the team’s opening series, Mirotic is the team’s x-factor because he inherently stretches opposing defenses. The team is 8-3 when he scores 20 points or more, and his very presence opens up opportunities for the team that they otherwise aren’t available. He’s willing to spot-up and knockdown a timely three-point field goal or pump-fake, put the ball on the ground, and attack the rim. There’s plenty of evidence suggesting Mirotic’s play makes Chicago a better scoring team. For example, during the regular season, Chicago’s offensive rating was 107.9 with Mirotic on-court, which dropped to 107.1 with him sitting. In the playoffs, the team’s offensive rating was unchanged when he sits.

Nikola Mirotic 2014-15 On/Off Stats (Team) | PointAfter

Plus, opponents see a rise in shooting efficiency, rebound percentage, assist percentage, and scoring with Mirotic off the floor.

Nikola Mirotic 2014-15 On/Off Stats (Opponent) | PointAfter

Mirotic’s length creates myriad problems for opposing defenders: His stretch-style of play and proficiency from beyond the arc means defenders have to respect his range (connected on 99 three-point field goals this season, third-most on the team), but he is equally proficient at taking them off the dribble and bursting into the maw of the defense (got to the free throw line 3.5 times per game, attempted third-most free throws on the team). In other words, he’ll be the ultimate nightmare for Kendrick Perkins if Cleveland’s big man ever is put into the game or switched onto him. Much of the defending responsibility will likely fall on Tristan Thompson.

As the following chart from Jacob Rosen notes, Chicago is more of a scoring threat when he is paired with either Joakim Noah or Pau Gasol, but not both. Thibodeau often plugs Mirotic into a long-ball lineup where he can be featured at power forward and exploit opposing paint protectors, which will likely be the approach against Cleveland without Love to defend him.

The Bulls enter their series with Cleveland having never had all five starters play at the same time in the team’s four meetings this season. Mirotic—who has the fourth-highest Player Efficiency Rating of any player in the league who averaged less than 25 minutes per game and logged more than 1,500 regular season minutes—is the x-factor that could propel Chicago to its first conference finals appearance since 2010-11.

Josh Planos has been published at the Wall Street Journal, the Atlantic, the Guardian, the Pacific Standard and VICE, among other publications. He has been heard on CBS Sports Radio, Fox Sports Radio and ESPN Radio. Planos is currently a Digital Editor at KETV NewsWatch 7 and a freelance writer.