But that was after the snoozer Juan Pablo Montoya made of the first 312.5 miles, until NASCAR snuffed his hyper-dominance with a penalty for speeding on the pit road.
Would Johnson have had anything for Montoya without the penalty?
"I don't have a clue," Johnson said, then snickered. "I do know I have the trophy."
Johnson essentially snatched it from Martin on the final double-file restart, which "changed the outcome," Martin said.
With Martin leading and Johnson restarting outside him, Johnson stayed side-by-side just enough to loosen Martin's car in Turn 1, and took the lead in Turn 2 with 24 laps left.
But Martin was by no means finished, closing and falling back, closing again and falling back again, attacking relentlessly down the backstretch of Indianapolis Motor Speedway until the end.
"Those last 15 or 20 laps, we had to drive it so hard to stay ahead of the 5 [Martin]," Johnson said. "I was better through 3 and 4, and he had me beat in 1 and 2, and it was kind of a give-and-take."
For a while Johnson zigzagged trying to break the draft on Martin, "weaving all around on the straightaway," Johnson said. "It didn't seem to make any difference, but at least I felt like I was doing something."
Agreeing on who was stronger in which set of turns, Martin said, "I knew I had to make it happen off 2. And I made some great runs, but I really thought several times I was going to hit the wall over there.
"And I absolutely couldn't go any faster," Martin continued. "In fact, I can't believe I didn't [hit the wall] on the third-to-last lap, and the last lap. I went through there beyond good judgment, to get a run. And it just wasn't good enough.
"I drove my heart out today -- but I just got beat by Superman," said Martin, who'd gotten a windfall win at Michigan in June after Johnson ran out of gas. But, "his cape don't get tangled around his neck much. He gets 'er done."
Johnson wouldn't don the cape, pointing out that he won because "clean air was everything," so the lead was the place to be. "You can only get so close to the car in front of you."
Tony Stewart, who finished third, doubted anybody would have caught Montoya if he hadn't been penalized. Acknowledging Montoya did have a clean-air advantage running out front, Stewart added that "he just consistently drove away from the field." Montoya built leads as big as 7.5 seconds at times.
Montoya maintained that "I was where I was on the previous one [pit stop] and they say I was speeding." But, added the driver who for a while overwhelmed this field even more than he had the Indy 500 field when he won it in 2000, "it is what it is."
Before the penalty, the race was what it was, between two classes of cars: Montoya's and all the rest.
Until Johnson passed Martin on that last restart, there had been only one pass for the lead under the green flag all day. That was when Montoya, starting outside pole-sitter Martin, took the lead on the fifth lap of the race and set sail.
Johnson, starting 16th, had to struggle up through midpack turbulence until Montoya's mistake. But, "it took me about two turns [after the start] to realize we had a very competitive car," Johnson said.
I drove my heart out today -- but I just got beat by Superman. His cape don't get tangled around his neck much. He gets 'er done.
”-- Mark Martin
"It was just very tough to come up through the field," he said. "At the end, with Juan having his problems and the caution coming out [on Dale Earnhardt Jr.'s blown engine], it gave me a chance to really race with Mark on the restart. That was my only opportunity."
But, "as I said, I have the trophy."
Johnson's supposed cluelessness about whether he could catch a penalty-free Montoya was because Johnson was so far back during Montoya's dominance that "I didn't run around him all day long," Johnson said.
But actually he did have a clue as to what might have happened, in that "on lap times we were on pace with what those guys were doing."
And so, Johnson's crew chief, Chad Knaus, said of the sluggish time in the turbulence, "we knew if we could get up there at the end we would have something for them."
Johnson became the first back-to-back winner in the history of this race, and has now won three of the past four 400s here.
Seven times in the race's history, the winner has gone on to win the season championship, so this one bodes well for Johnson's run at becoming the first NASCAR driver ever to win four Cups in a row.
And this, his third win of the season, is second only to Martin's four when it comes to seeding for the Chase.
Plus, he moved past another Hendrick Motorsports teammate, Jeff Gordon, who finished ninth Sunday, in the point standings. Johnson is now second, 192 points behind Stewart.
The weekend here didn't start out well for Johnson's branch of the Hendrick juggernaut, and it was Martin's branch that came to the rescue during practice sessions.
"We had to dig pretty deep," Knaus said of getting the car to handle well on the flat, rectangular old track here. "Alan Gustafson [Martin's crew chief] and the guys on the 5 team were a big help to us. We took some lead from some of the stuff they were feeling throughout Friday and Saturday. We were able to apply it. "
So in addition to shrugging off Montoya's failed onslaught, they beat Martin's branch of the team with its own information.
But they have the trophy.
Ed Hinton is a senior writer for ESPN.com. He can be reached at email@example.com.