Newcastle came from behind to beat Liverpool as both sides served up a memorable game in awful conditions.
Martins scored his 12th goal of the season
Steve Harper's poor clearance was seized upon by Jermaine Pennant, who set up Craig Bellamy, as the Liverpool striker scored against his old club.
Pepe Reina was equally at fault when his misjudged clearance was pounced on by Obafemi Martins, who sidefooted in.
But Newcastle snatched the victory when Nolberto Solano scored with a penalty after Steven Taylor was fouled.
The driving rain and the sodden pitch might have produced plenty of mistakes, but this end-to-end game was all the better for that.
It had the feel of a match from a bygone age - voluminous support from both sets of fans encouraging their respective teams to go for the jugular at every opportunity.
Liverpool had the better of the first half, but Newcastle hung in and more than matched Rafa Benitez's side after the break.
Newcastle finally edged ahead on 70 minutes when John Arne Riise was adjugded to have fouled Taylor, with Solano calmly converting the penalty.
In the closing stages Liverpool laid seige to the Newcastle goal, but the home side kept their heads to seal the win.
As so often this season, Liverpool were let down by Reina's inconsistent goalkeeping and an inability to convert a series of good chances.
Bellamy might have scored a hat-trick in the closing stages of the first-half, while Dirk Kuyt should have done better after the break when he only had Harper to beat.
The Wales striker did not take long to make his presence felt on his first return to St James' Park in over two years
Put under pressure by Bellamy, Harper's clearance went straight to Pennant, who quickly exploited the sense of panic caused by the Newcastle keeper's mistake.
Pennant quickly got to the byline before cutting the ball back to Bellamy, who sidefooted home.
Reina has had his fair share of blooper moments this season and on 26 minutes he served up another whopper to the delight of the Newcastle fans.
Rushing out of his area to clear the ball, Reina's clearance hit Daniel Agger, falling conveniently into the path of Martins, who side-footed home.
The rest of the first half proved a personal duel between Bellamy and the Newcastle defence.
The Liverpool striker hit the bar with a shot and almost scored after rounding Harper only to have his final shot cleared.
Bellamy's pace also allowed him to get the better of Titus Bramble but he was unable to find Kuyt with his cross.
Newcastle manager Glenn Roeder on the death of Celestine Babayaro's brother:
Celestine called me yesterday. His younger brother has been suffering from tuberculosis and he had lost his life.
"After consulting his older brothers they thought his younger brother would have wanted Celestine to play.
"Our supporters should know that because that does take courage."
Liverpool manager Rafael Benitez:
"After the first half, the score could have been 0-3 or 0-4.
"But we conceded a stupid goal and then a stupid penalty, and after that, it is difficult to win.
"We created enough chances, very clear chances to win. When you play away from home and you have three or four chances."
Newcastle: Harper, Taylor, Onyewu, Bramble, Babayaro, Solano (Duff 86), Parker, Butt, Milner, Dyer (Sibierski 81), Martins.
Subs Not Used: Srnicek, Luque, Huntington.
Goals: Martins 26, Solano 70 pen.
Liverpool: Reina, Finnan (Crouch 84), Carragher, Agger, Riise, Pennant (Arbeloa 76), Sissoko, Gerrard, Zenden (Guthrie 75), Bellamy, Kuyt.
Subs Not Used: Dudek, Hyypia.
Goals: Bellamy 6.
Ref: M Halsey (Lancashire).