The second unit has been an important part of coach Brad Stevens game plan ever since he came to the Boston Celtics. That is one of the things that sets him apart from many coaches, for whom the game plan is mostly based on the starters and playing the bench is a necessary evil. A few other coaches pay the same attention to their second units, with San Antonio's Gregg Popovich as the most prominent among them.
The balance betwen the first and the second unit is probably the reason why we've seen Brad Stevens tinkering with his lineups long into the regular season. He seems not to be satisfied until both his starters and his bench are in harmony.
Unique Skill Sets Set Them Apart
Right now the three main cogs in the machine that is the second unit are Marcus Smart, Evan Turner and Kelly Olynyk. Jonas Jerebko is important too, for stretching the floor, but he can be replaced by Avery Bradley or Jae Crowder depending on matchups. Lately, Tyler Zeller has had a renaissance with the second unit, where he is valuable on defense and as a screen setter both in the pick-and-roll and off the ball.
But, as mentioned above, it is Smart, Turner and Olynyk who are the three most important players in the second unit. While Jerebko and Zeller are complementary players, the other three possess individual skill sets that are unique when you add size and other physical attributes. This can creat huge matchup problems for opponents, especially against weaker second units.
The trio haven't played as many minutes together as Turner, Olynyk and Jerebko, but that's primarily because Marcus Smart has been injured and missed 21 games so far this season. Even at 338 minutes so far, according to Basketball-Reference.com, it's the 15th most used 3-man unit with the Celtics and has produced a +7.4 net rating per 100 possessions.
Marcus Smart Uses His Superior Physique
If you look at the NBA map, you'll find many smaller guards in the second units, which gives Smart the opportunity to bully them on both ends of the floor. It is obviously most effective when the Celtics play defense because the Celtics can use him against many different players depending on their game strategy.
A couple of weeks ago, we saw an intelligent counter-move by Orlando Magic's Scott Brooks, who chose to pull his small guards against the Celtics second unit in the second half of the game, opting to go with the 6'8'' Mario Hezonja as a primary ball handler. The Celtics didn't find the response to this move, and Orlando was able to turn the game around and win it.
On offense, Marcus Smart took his time this season, but he had an 11 game hot streak from behind the arc leading up to the All-Star break, hitting almost 43 percent of his three pointers while attempting more than five per game.
Evan Turner Needs Shooters Around Him
Evan Turner's game is certainly flawed, but he does almost everything well, except for shooting three pointers. And as a 6'7 ball handler, he is usually a handful for the defense, but only when surrounded by shooters who can create the space for his attacks to the rim. Lately he has been lethal around the rim, using his right hand on both sides of the basket.
Turner's defense has been very good all season. It probably helps him that he has a size advantage against most guards.
Kelly Olynyk Is A Big Man With Guard Skills
Kelly Olynyk has been drawing a lot of attention this season, and deservedly so. With his three-point ability, he can create space like a stretch four, except that with his size he is more like a stretch five. And because of that size, his guard-like ball handling and passing are huge advantages on offense. Very few seven footers have that footspeed, and those who have it are coveted as defensive stoppers and mostly used as starters.
The biggest improvement for Olynyk is, however, his defense. Even at the beginning of this season, it was obvious that his hard work during the summer had paid off. It's no coincidence, that he has the best on/off court differential on the defensive end for this roster with an impressive +6.4 points per 100 possessions. This means that the opponents offensive rating has been 6.4 points lower when Olynyk has been on the floor. There are obviously many explanations for that, but it can't be ignored that much of it comes from his individual skill.
In his rookie season, many people deemed him to be slow on his feet. That might have been true, but not anymore. He is actually very nimble for a seven footer and he's rarely out of position, which was probably his main problem coming into the league.
The Bench Comes Through In Crunch Time
This season, we've seen all three players take over games with their special skill sets, even against the opponents' starters. They are simply matchup nightmares.
The following video is from last season, but it's a great example of one of Evan Turner's strong sides. He's never afraid of the moment, which makes him a great player in crunch time.
So far this season, Boston has played 30 games that ended in crunch time (point difference at five points or less within the last five minutes of the game). Turner has seen the floor in 24 of those games, averaging 3.0 minutes in crunch time, while Smart and Olynyk have played in crunch time in 17 and 16 games respectively, both averaging 1.9 minutes. Again, Smart has been out for almost half the season.
Among those who have played regular crunch time minutes, Turner is actually the only Boston player with a positive net rating in crunch time, according to NBA.com.
They're far from being a ”Big Three” in the traditional sense, but for bench players, they're probably as big as they come.