Russell Martin said Swansea City had achieved “an incredible feat” after they made more south Wales derby history with a pulsating 3-2 to win at Cardiff City.
The Bluebirds were set to halt their run of misery in this fixture after fighting back from 2-0 down.
But Ben Cabango’s 99th-minute goal gave Swansea a fourth straight derby win.
“From no-one doing two in a row to then doing four is an incredible feat for the players,” said Swansea boss Martin.
“I am really proud of them because they have written themselves in the history books.”
Neither club had managed a league double in the south Wales derby until last season, when Swansea won 3-0 at home and 4-0 at the Cardiff City Stadium.
Martin’s team have now delivered a double double, having triumphed 2-0 at the Swansea.com Stadium last October.
Cardiff looked to have earned what might have been a crucial point in their fight to avoid relegation after Sory Kaba’s 84th-minute header made it 2-2.
“It’s hard for me,” said Cardiff boss Sabri Lamouchi.
“But trust me, it’s hard for the players. They tried to find the right words to keep their heads up, but it’s not easy.
“The atmosphere in the locker room is absolutely different than the opponent’s locker room.”
Defeat means Cardiff are only outside the Championship relegation zone on goal difference with eight games remaining this season, the first of which comes at 23rd-place Blackpool next Friday.
Cabango’s winner came nine minutes into added time despite the fourth official’s board showing only five.
Asked whether he was surprised the game was still going on, Lamouchi added: “Yes but what can I say? We spoke with the referee, we ask him, he played more than five minutes.
“We can just accept the wrong decision against us in this moment. Shut up, head up and work.
“We need to focus on that. The way we played, the way we fight, the way we came back in the game is very positive.”
Martin said Swansea’s triumph was especially satisfying given the difficult run they endured before beating Bristol City prior to the international break.
“I said that to the players before the game today, we are going to win and win our way, and that will be the best feeling,” he added.
“We didn’t come here and dog it out and fight. We didn’t do that against Bristol City when we were in a tough period and were getting loads of criticism from all angles.
“We have stuck to what we want to be, the players have been incredible.”
Martin also paid tribute to Morgan Fidler, a three-year-old Swansea fan who is undergoing treatment for cancer and was carried onto the Cardiff City Stadium pitch before kick-off by captain Matt Grimes.
“We spoke about it before the game, little Morgan who was our mascot today,” Martin added.
“We sent him a video yesterday. What he’s been through already in his early life at three years old is so difficult and puts things in perspective.
“So we spoke about trying to give his family a special day and I’m so grateful we could do that.”
