Boston's small-ball strategy has shifted the momentum of the series

When you go down 2-0 in a playoff series, you need a response. You need to counter your opponents strengths to slow them down. Chicago was crushing the Celtics on the glass in their opening two victories, and Brad Stevens had an unorthodox lineup change in response. Instead of focusing more on the rebounding issue - which Boston has been notoriously bad with all season - Stevens decided to force Fred Hoiberg and the Bull's hand by going the complete opposite direction.

Sure, Robin Lopez. You can have your rebounds. We will just spread the floor with small-ball lineups and beat you with speed and shooting.

It began when Stevens announced that Gerald Green would be making his first start of the season in place of Amir Johnson for Game 3. This was a real head-scratcher for many, not just because he hasn't started all year, but because Boston was already struggling in the paint and replacing a big man with a wing player would surely not help. But this lineup change, along with Stevens' overall shift to small-ball lineups, has totally changed the momentum of the series.

The versatility of the small-ball Celtics has allowed them to switch much more effectively on defense. It has opened up the paint that had been clogged in Game 1 and 2, giving Isaiah and company the ability to attack, find open shooters, and make plays happen on offense. This was evident in Game 3 when Boston knocked down 17 threes and assisted on 34 of their 41 field goals.

Coach Stevens put more emphasis on going small in Game 4. Johnson was completely held out of the game as a Coach's Decision for the first time all year, and Tyler Zeller failed to hear his name called. It has been Green and Terry Rozier taking their minutes in the spirit of their small-ball approach.

In Game 3 and 4, Boston's new starting lineup shared the floor for 29 minutes and had a team-best +15 in the box score. That is nearly twice as high as the next best lineup - which also happens to be a small-ball lineup - of Marcus Smart, Rozier, Avery Bradley, Jae Crowder, and Al Horford.

While Green has been huge as a starter, Rozier has also been a crucial part of the smaller lineups' success. He put up a playoff career-high 11 points while converting three three-pointers in Game 3, and has continued splashing home shots from deep at a very high rate. The Celtics have by far played their best when the second-year guard is on the hardwood:

Along with Rozier, what perhaps makes the small-ball lineups work so efficiently is Horford's impressive versatility as a big man. His ability to spread the defense with perimeter shooting, to put the ball on the floor, and to make the right pass at 6'10" makes him a valuable part of this strategy. Bringing out Kelly Olynyk or Jonas Jerebko, two players who have similar small-ball attributes as Horford, carry this role when Horford is getting his rest on the bench.

Boston has clearly figured something out with their lineups against the Bulls so understandably, Stevens seems to be sticking with this strategy for Game 5:

Follow Erik Johnson on Twitter: @erikjohnson32

Photo by @Celtics