The 32-year-old made it clear he is unhappy with many aspects of his employment by the England and Wales Cricket Board, and is prepared to risk his Test future to put them right.
A man-of-the-match performance in the second Investec Test at Headingley could not avert a stalemate which leaves England 1-0 down with one to play against South Africa, and needing to win the final Test of three to preserve their world number one status.
Pietersen's 21st Test century did give him the platform to voice his discontent, though - albeit after first insisting several times over he had no intention of discussing his stand-off with the ECB.
His shock retirement from all limited-overs international cricket in June followed a breakdown in negotiations over his gambit to ditch 50-over matches but remain a Twenty20 batsman.
The ECB stuck to their principles then, and can be expected to play hardball again with a world-class cricketer who has been no stranger to controversy throughout his eight-year international career to date.
Asked on BBC Test Match Special to confirm the decisive Lord's Test will not be his last, Pietersen said: "I can't give any assurances.
"I would like to carry on, but there are obstacles that need to be worked out."
Many have portrayed his gripes as financially-orientated, but he denies those suggestions.
"It's absolutely 100% not about money. This is not a money issue," the 32-year-old said.
"There are clear things that I'm discussing. But there are other issues that need to be sorted."
Pietersen also disputes the idea that the sticking point is his desire to be available for a full Indian Premier League campaign next year - at a time when England have Test match obligations.
"That is two of many points - and they're not the main two points," he said.
"Let's get that very clear. They're not the main two points - there are other points I'm trying to sort out in the dressing room."
Pietersen refused to go into detail about his disenchantment, yet risked alienating public opinion by inviting pity.
"You know what, for me, the saddest part about all this is that the spectators just love watching me play - and I love playing for England," he said.
"The politics is what I have to deal with personally. It's tough being me playing for England."
Captain Andrew Strauss spent several uncomfortable minutes dodging all questions about Pietersen's problems, and their likely effect on England before such an important match.
"I don't want to talk about what Kevin may or may not have said," the skipper said.
"I hope the Kevin issue isn't going to be a distraction. The truth is we want as few distractions as possible in making sure we win this third Test match.
"One thing I will say, and it is important to stress this, is that the team unity we have had over the last three years has been outstanding.
"It is something we all pride ourselves on, always have done and will continue to do so."
Strauss will do well to ensure his and coach Andy Flower's treasured team ethos is intact - with or without Pietersen - especially once the mercurial South Africa-born batsman's latest comments have been properly digested by ECB management.