Five reasons why the Boston Celtics should keep Marcus Thornton

Earlier this month I wrote about why the Boston Celtics should trade the recently acquired Marcus Thornton in order to free up more minutes for other young players at the wing position, but it's easy to forget that Thornton himself is relatively young, at just 27-years-old.

Thornton is a score-first shooting guard and still has the potential to be a quality player, which is one of the primary reasons why the Celtics should consider keeping him.

Thornton's a sparkplug

This is what I wrote before free agency began earlier this summer:

Offseason Preview: Guard Targets
After selecting Marcus Smart at #6 in the 2014 NBA Draft, the Celtics managed to bolster their backcourt depth, but they still need to fill the role of "sparkplug," a position that Danny Ainge has had every single season of his tenure as general manager. Seriously, just look at that list to the right. There's no question that Boston will be active in their pursuit of a scorer who can light it up from the guard position; thankfully, there are a load of options...

Even though Boston didn't add a sparkplug scorer in free agency -- Evan Turner can in spurts -- there is no doubt that Thornton can fill that role. That is what his game is built for -- his nicknames are "Bayou Bomber" and "Buckets" for good reason. Over the years he has gained the reputation of being a one-dimensional shot chucker and a volume scorer, but these are derogatory terms. Another appropriate term could be sparkplug, which is what the Celtics needed.

Thornton will definitely have his off-nights, but he will also have games where he starts bombing away from downtown and goes off for 30-plus points. He's the type of player who can win a game because of his scoring spark off the bench, or at least bring momentum back in Boston's favor.

Marcus + Marcus = Production

Let's think about the other Marcus on the team -- Marcus Smart, that is -- what is the best way to help him develop into more of a true point guard? I'd argue that it's pairing him with a player who can score off of him and drain open three-point opportunities.

Naturally, Thornton fits that description to a tee. Thornton has attempted 790 spot-up threes in his career and sank 38.1 percent of them. This is a terrific weapon that will help the Celtics, who ranked 27th in the NBA on catch and shoot threes last season, according to SportVU.

Smart is at his best in space, so it'll be interesting to see him running the floor with Thornton, who hits threes at a 37.6 percent clip in this situation. If the bench is able to force turnovers, the Marcus Duo could be extremely potent in transition.

Thornton could be a late bloomer

Believe it or not, Thornton was once thought of as one of the league's promising young scorers after averaging 18.7 points with a 50.5 eFG percentage as a third-year player. Even though his points still came in bunches, he flashed the potential of a high-end role player.

Two years later, Thornton is an outcast; his defense has degraded and his efficiency has plummeted. But what has also evaporated is any semblance of a consistent environment. Thornton's role and minutes have fluctuated so much so that he has been unable to establish any sense of a rhythm.

Situation	eFG%	3PT%	2PT%	FG%	PTS/36
Over 30 Minutes	51.6%	37.1%	49.2%	44.6%	19.7
20 to 30 Minutes	52.0%	37.6%	48.7%	43.9%	18.5
Under 20 Minutes	38.4%	25.6%	38.4%	33.6%	13.2
Starter	50.0%	34.9%	48.5%	43.2%	17.9
Reserve	50.6%	37.1%	47.2%	43.0%	19.0

The chart above suggests a couple interesting things about Thornton. First, he is a total non-factor unless he's playing at least 20 minutes per game. He has a dismal 38.4 eFG percentage in games playing less than 20 minutes per game, but that percentage rises to over 51 percent in games he plays 20 minutes or more.

This could mean that he just gets pulled when he's struggling (so he's not able to reach the benchmark of 20 minutes), but it could also mean that he takes awhile to develop a rhythm, like many shooters do. Considering the abnormally huge disparity in numbers, I'm willing to bet that it's more the latter than the former. However, a more in-depth study would be necessary to determine the true cause.

It's quite reassuring there is no discernible difference in his numbers when he starts or comes off the bench, since Thornton will have a reserve role with the Celtics this season. Many score-first players have difficulties finding the flow when they aren't starting, but Thornton appears to have adjusted well.

Thornton is an expiring contract

Even if Thornton has another disaster of a season, then that's really the worst that can happen. With an expiring contract valued at $8.6 million, he could hold some value closer to the deadline trade deadline.

Even if the Celtics struggle again this season and are sellers closer to the deadline, then there's a chance some team will look for a low-risk, high-reward scorer like Thornton. Maybe the Celtics could be in a spot to acquire a draft pick or young player, just like they did for Jordan Crawford last season. The return wouldn't be strong, but it'd be a lot more than they'd get now (which is next to nothing).

Or think about the best-case scenario: What if the Celtics are having a good season and are in a position to make a move for a big-time difference-maker? Is there another team in the league who can offer an expiring contract (like Thornton)? Sure, but there aren't very many who have the assets to complete a deal. If Danny Ainge wants a player, he might be in the best position to get him.

There is no reason not to plan for the best-case scenario, especially if the front office really does want Rajon Rondo to be a part of their long-term plan.

Even putting aside any potential trades, Thornton is a fairly young player who once flashed the upside of an effective scorer who can create his own shot on a nightly basis. He has faded in recent years, but if the Celtics keep him on the roster for the year, they might find out that they want to keep him around longer.

The Bayou Bomber hits big buckets

Boston was 9-14 in games decided by five points or less last season, partially due to their inability to get stops, but also because of the lack of a go-to scorer down the stretch. They were the 27th ranked team in eFG percentage in games in the last three minutes of games with a point differential of five or less. Of qualified players, Jeff Green was the most "clutch," with a 44.4 eFG percentage in the aforementioned situation.

But Thornton takes the cake, with a career 47.6 eFG percentage in that specific situation. He has nailed tons of daggers and appears to live for those moments. Even though Green was solid in that role last season, he still really isn't the type of player who can create is own shot. Thornton can, which presents value in end-game situations when Brad Stevens can use his timeouts to substitute in offense-oriented players like Thornton.

If Marcus Thornton isn't traded before the season, then he'll certainly get the chance to "showcase his talents" with the team, but he'll need to put forth the same effort required on the defensive end for Stevens to give him heavy minutes. If he does that, he might be one of the Boston Celtics' greatest surprises.

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