Brad Keselowski feeling the heat?

CHARLOTTE, N.C. -- A group of rambunctious children banged hammers provided by Jimmie Johnson's primary sponsor to the point it almost drowned out the five-time Sprint Cup champion as he was being interviewed at the NASCAR Hall of Fame.

It was almost deafening, similar to the noise Johnson heard on Sunday as crewmen hammered out sheet metal on the back of his No. 48 Chevrolet to turn a near disaster into a potential Chase-winning moment.

"Ron was hitting it a heck of a lot harder than that," Johnson said of car chief Ron Malec on Tuesday. "He was clobbering the car. I'm like, 'Dude, you're going to break something else! Stop hitting it so hard!'"

As the pounding continued, Johnson turned to the group of reporters surrounding him on the balcony above the young carpenters and said, "Is that killing you, guys?"

Everyone nodded.

"That's awesome," Johnson said with a devilish grin.

That also was symbolic. Johnson plans to keep banging away at the slim point lead Brad Keselowski holds over him with four races to go in the Chase. He hopes the noise becomes so deafening that it gets into Keselowski's head to the point the Penske Racing driver makes a mistake.

It happens, you know.

Two years ago, Denny Hamlin appeared a shoo-in for the title until a miscalculation on fuel turned a potential win and near Chase-clinching moment with one race to go at Phoenix into a total collapse at Homestead.

A year ago, Tony Stewart came out of nowhere to win at Martinsville and immediately threw down the gauntlet to points leader Carl Edwards, saying, "He better be worried, that's all I've got to say. He isn't going to have an easy three weeks."

Finishing off a championship never is easy, particularly if it's your first. Johnson had trouble finishing the job during his first four seasons, going fifth, second, second and fifth before beginning his run of five straight titles.

Hamlin and Edwards failed to do so the past two years.

Now it's time to see if Brad Keselowski can.

"I want to believe we'll creep into his head and the things I went through would be the same for others, but we're all wired differently and respond differently to pressure," Johnson said as he moved into an adjacent room to escape the noise of the hammers.

As calm and cool as Keselowski has remained through the first six Chase races, as flawlessly as he's driven while building a seven-point lead over Johnson heading into Sunday's race at Martinsville (2 p.m. ET, ESPN), history tells you the pressure will get to him at some point.

Until now, the pressure has been minimal, as everyone has positioned themselves for the stretch run. Now, everything is magnified. Now, the pressure is intensified.

Each little mistake seems more costly because there is less time to recover.

Johnson once felt it. Odds are Keselowski will feel it, too.

Maybe he already is. The jabs he took at the No. 48 team about the car's rear housing advantages during the regular season have stopped. Many of his colorful quotes have switched to clichés about taking it one race at a time, although he did get in a good plug for his sponsor after surviving Kansas by saying "I can't wait to go home and have a couple of beers."

"It catches up to you at some point," Johnson said. "It does. When you're leading, it's hard to push out of your mind. Every media guide they remind you of being the points leader and that you're fighting for your first championship.

"At some point, the magnitude of being champion sets in. I've had to live that fire myself. We'll see how everybody handles it."

That was Johnson's subtle reminder to Keselowski that he's lurking, that he better not make a mistake. Subtlety is Johnson's specialty. He won't hammer Keselowski over the head as Stewart did to Edwards, as Kevin Harvick did with Hamlin.

"When I was younger, anytime I was cocky, arrogant, full of myself, it always backfired on me," Johnson said. "Since then, it's take care of my work on the track. Let it speak for itself."

Johnson's performance typically puts that added pressure on the Chase leader. Kansas was the perfect example. After a wreck that almost killed his title hopes, the crew rallied to fix the damage and Johnson rallied for a ninth-place finish.

"Listen, there's a reason why they're five-time champions," Hendrick Motorsports teammate Jeff Gordon said.

As Gordon correctly noted, more championships are won by how a team turns a bad situation into a solid day than how many times they visit Victory Lane.

But Johnson can turn up the heat with wins, too. In 2007, Gordon was 68 points ahead under the old system and coming off a victory at Charlotte. Johnson won the next four races to go into the finale with an 86-point lead.

"You might get deflated [by what Johnson's team did at Kansas]," Gordon said. "But that will do it way more in a hurry, far more than it did on Sunday."

Martinsville will be key. Johnson is almost unflappable there. He has six career wins and an average finish of 5.8.

In eight Chase races, he has four wins and an average finish of 2.0 on this half-mile track in the Virginia foothills.

That's significant because of the eight Chase champions, four won at Martinsville, two finished second and none finished worse than fifth. Johnson never has finished worse than fifth in a Martinsville Chase race. Keselowski never has finished better than ninth there -- period.

"For Brad, yeah, the pressure is on," Gordon said.

Before you read into this as a couple of HMS teammates ganging up on the competition, Gordon isn't so sure Keselowski will crack under the pressure.

There are many reasons to believe he may be right.

"Each race that goes by and Brad maintains the points lead, the pressure is going to build on him," Gordon said. "And when you're Jimmie, you've won it all different ways. There are very few surprises.

"But [Keselowski's] not the kind of guy that to me cracks under pressure. He lets the performance and actions speak for themselves for the most part. … To me, his performance this weekend was equally as impressive as Jimmy's."

We thought the same thing about Hamlin in 2010. He left Martinsville with a win and a swagger that seemed unbeatable. He said the pressure was on Johnson, not him.

Then the pressure beat him, first with the fuel mileage at Phoenix and then an unforced spinout at Homestead that turned a 15-point lead into a 39-point deficit.

"The position someone is in without being champion previously, you're wondering, 'What do I need to do? What's that road map look like?'" Johnson said. "No one is immune to it. I guess it just affects your sleep at night.

"Experience helps you be more calm."

The hammering in the background had ended, but Johnson will keep hammering at Keselowski.

How the 28-year-old handles it will determine who wins the title.