OKLAHOMA CITY – Reggie Jackson is on the accelerated learning program. It did not come by design.

In the course of his sophomore season, the Oklahoma City Thunder point guard was twice sent to the Tulsa 66ers of the D-League in December after averaging 6.9 mpg in 14 games with OKC, and came back and beat out Eric Maynor (eventually traded to Portland) for the right to back up Russell Westbrook.

“When you’re playing behind an All-Star point guard, the minutes are tough,” Thunder coach Scott Brooks said. “But we somehow managed to give him 15, 16 minutes a game.”

Those minutes, mostly all spent directing the second unit, are invaluable now as Jackson has stepped into the unenviable role as the injured Westbrook’s replacement, logging more than 30 pressurized playoff minutes a game.

Jackson’s task is to lead the Thunder offense, seek a balance between being an aggressive playmaker and driving to the paint, feeding — and also getting out of the way of — MVP runner-up Kevin Durant, defending Memphis Grizzlies point guard Mike Conley and not melting in the glare of the postseason klieg lights.

Jackson’s studying more film and being coached harder. The three-day break between Games 2 and 3 in this semifinal series, knotted up at 1-1, might have been most beneficial for Jackson as he processes information from multiple angles and sources.

“Oh yeah, Coach Westbrook is doing a good job, watching the game, observing,” Jackson said, breaking into a smile. “He’s definitely on me a lot about pedal-to-the-metal and just trying to make plays for others and myself, try to take the load off Kevin.”

Yep, pedal-to-the-metal sounds like Westbrook. Of the many injured stars out of the playoffs, perhaps none is as uniquely dynamic for their squad as Westbrook is for the Thunder. He’s the bullet-train engine that powers OKC’s high-paced offense and keeps defenses backpedaling with powerful bursts up the floor and a pogo-stick, pull-up jumper. His active perimeter defense can be equally as fierce.

“I’m definitely talking to Reggie a lot more, but I also want him to learn and get better,” Westbrook said Thursday during his first public appearance since undergoing knee surgery on April 27. “You don’t want to tell a guy to go out there and do all these different things, you kind of want him to learn, and it’s a learning process for him as well as for me.”

And so, arguably, none of the players filling in for injured stars are being asked to fill quite the vacuum as the 6-foot-3, 208-pound Jackson.

That grand-canyon sized leap he’s making from hold-the-fort reserve to starting  point guard on a team with championship aspirations is intense and potentially mind-spinning. That it came with little time for Jackson and the team to absorb the full magnitude of Westbrook’s season-ending knee injury, to indoctrinate Jackson into the starting lineup and for Brooks to tweak his rotation, is a tremendous challenge. Fortunately for the Thunder, 38-year-old Derek Fisher, signed in late February, has been hot off the bench, easing some of Jackson’s burden.

“I had 24 hours, that’s good enough,” said Jackson, the 24th pick in the 2011 draft out of Boston College. “But it’s basketball. Remember, I started at some point in my career. I understand that coach trusts me, obviously, enough to play me in this moment and to take a new role. He sees something in me; my teammates do, they’re always on me, encouraging me, so I just got to go out there and have fun and just play basketball.”

Jackson, who said his name bears no lineage or linkage to baseball’s Mr. October — which could have come in handy in this situation — is averaging 30.9 mpg in the playoffs, more than doubling his 14.2 regular-season minutes. He averaged 21.0 mpg in the first two playoff games with Westbrook playing, and 31.2 mpg as a starter. He took 11 shots in the first two games. He’s averaging 11.6 since.

He averaged 14.0 ppg in the six games against the Rockets and shot a healthy 46.2 percent from the field. He has produced six consecutive double-digit scoring games. However, against the Grizzlies’ sturdy defense, Jackson has found the space on the floor shrinking and multiple, wide-body blockades in the paint, two vast differences from playing the wide-open, up-tempo Rockets. He’s averaged 11.0 ppg on 43.8 percent shooting against Memphis.

“He just has to play within what his capabilities are,” Brooks said. “If there’s openings, he has to attack. If he has that in transition, great. If he has that in the halfcourt, great. I think he is better when he does attack, he’s a great finisher around the rim.”

And then there’s the other end of the floor. Under normal circumstances, Westbrook and Conley would be facing off in a fascinating duel, and Jackson would mostly be sticking to the streaky shooting Jerryd Bayless. But now the sixth-year and ever-improving Conley, who has juiced his stats to 17.9 ppg and 7.8 apg in the playoffs, is Jackson’s responsibility.

The youngster took Conley’s explosive fourth quarter in Game 2 that nearly netted him a triple-double and pushed the Grizzlies to a 99-93 victory, as a personal affront.

“I can’t let that happen again,” Jackson said. “I feel that great players always take things personal, their matchups, and since Day 1, I always said that I want to be great. I have to do a better job of slowing him down and not let the head of the snake bite us next game.”