Backup engine for this JET

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Jason Terry keyed the second-unit offense in San Antonio on Saturday.There have been times this season when Celtics coach Doc Rivers has seemed downright apologetic while discussing Jason Terry's role at the start of his time in Boston.

Terry, the former Sixth Man of the Year who was recruited specifically to provide a much-needed bench spark, had been thrust into a starting role for the first quarter of the season as the team attempted to bridge the gap until Avery Bradley's return.

With Bradley (shoulders) seemingly inching closer to being cleared for contact activities, Rivers shifted Terry back to a reserve role the last two games and -- despite the Celtics losing both ends of a Texas back-to-back in Houston and San Antonio -- Terry showcased the boost he can provide the second unit.

Terry erupted for 17 first-half points on 6-of-8 shooting during Saturday's game against the Spurs, joining forces with Paul Pierce to carry the Celtics over the first 24 minutes. He missed his final five shots while finishing with 18 points and four assists over 31:21, but he was one of the few Boston players that logged big minutes and landed on the positive side of the plus/minus totals, hammering home his impact in a 103-88 loss.

Look closely at the lineup data and you'll see the jolt he provided the offense. A lineup with Terry, Jeff Green and the Big Three was 7-of-11 shooting for 18 points (plus-2 overall) over seven minutes (only the starting group with Courtney Lee and Brandon Bass logged more floor time). Another lineup with Terry, Green, Pierce, Rajon Rondo and Chris Wilcox was 5-of-7 shooting for 11 points (that lineup finished even with the Spurs over five minutes of floor time).

But two reserve-heavy lineups that played minor minutes gave a glimpse of how Terry can keep Boston afloat when its Big Three is off the floor.

An intriguing combination of Terry, Green, Lee, Kevin Garnett and Leandro Barbosa emerged plus-5 over three minutes. Sub Jared Sullinger into that lineup for Barbosa -- giving it more size balance -- and the unit was plus-4 over three minutes.

Part of the reason Rivers was seemingly reluctant to move Terry out of the starting lineup was the offensive boost he gave the unit. Boston's offensive numbers have been off the charts -- particularly compared to recent seasons -- and Terry's ability to both hit open 3-pointers and create off the dribble has been a nice luxury.

According to Synergy Sports data, Terry is averaging 1.067 points per play to rank in the 93rd percentile among all NBA players. Narrow that list to guys with a minimum on 200 plays this season and Terry ranks 11th in the league, tied with Carmelo Anthony and with only the likes of Kevin Durant (2nd, 1.125) and LeBron James (6th, 1.07) in front of him. Yes, old friend Ray Allen is second overall at 1.176 points per play, but Terry is helping defray what Boston lost offensively with Allen's departure.

And here's a mild surprise: Terry has been a more competitive defender than expected (though, the bar was admittedly low). His numbers are not great -- he ranks in the 46th percentile among all NBA players while allowing 0.864 points per play -- but he's been a solid pick-and-roll defender, an area that Boston struggled with early in the season. And his energy has been infectious.

For Terry -- like the Celtics as a whole -- it comes down to consistency, and that was encapsulated in Saturday's performance with a big first half and quiet second. At age 35, there will be fatigue issues -- Boston is no stranger to that -- and it's on Rivers to find the right balance of minutes. But the return of Bradley, and having Barbosa as an emergency body, should allow Rivers to find a comfortable number that allows Terry to be more consistent.

Terry's assist rate also is way down, but he had four helpers versus San Antonio, an encouraging sign that he can fuel the second-team offense when Rondo is off the floor. Terry's presence might further aid the likes of Green -- and even Lee when he shuffles back to the second unit -- in generating quality looks.

Rivers was forced to lean on Terry heavy at the start of the year, taking him out of his comfort zone, but he's still found a way to contribute. If he finds that consistency, JET could really take flight.

Heck, he admitted as much before this road trip.

"I know for me personally, just being consistent with my shot and making sure I'm taking and making a good shot," he said. "So if we can put it all together for 48 minutes, I think that that's when we'll start to get the results."