Heading into the game, Fenerbahce were in the territory where they couldn't afford to drop a single point. Coming into an Istanbul derby against Besiktas presented an opportunity to prove that, with a win, they were going to take the title race down to the wire.
Besiktas have struggled all season, but since Ole Gunnar Solskjaer arrived, their performances in the bigger games have been far better than against the smaller teams. With victories over Trabzonspor and Galatasaray (whose only defeat this season came against Besiktas), they have enjoyed playing against sides that give them more space.
Ole made a key change to his side for the game. In order to bolster the midfield and get Gedson Fernandes into more dangerous areas of the pitch, he paired Amir Hadziahmetovic and Alex Oxlade-Chamberlain together just in front of the defence, and pushed their Portuguese star into the number 10 role just behind Rafa Silva up front.
And the change worked for Besiktas. In the first half, despite having a little less of the ball, they were a strong threat on the counter, and they didn't really let Fenerbahce have too many clear-cut chances.
Gedson missed a penalty early in the game after having lasers shone in his face, however, he soon made amends, pouncing on some really poor defending from Mert Muldur to slot home for Besiktas.
The second half saw even more backs to the wall defending as Fenerbahce made several attacking changes to get them back in the game. Centre back Gabriel Paulista was absolutely monstrous in defence, as was Arthur Masuaku, who started the game next to Paulista before moving to his favoured left back later on.
Goalkeeper Mert Gunok was the hero of the match, though, with the 36-year-old making a number of excellent saves. Turkey's No. 1 was imperious all game.
Anderson Talisca, Edin Dzeko and Dusan Tadic all knocked on the door, but Mert wouldn't let them in.
The full-time whistle finally blew, and Besiktas hung on for a 1-0 win. While not mathematically out of their reach, the Super Lig title was gone for Fenerbahce at that very moment. Everyone knew it, as players and fans cut distraught figures.
Eight points behind with four games left of the season is too big a mountain to climb, especially with Galatasaray in top form.
It has now been 11 years without the Super Lig title, and fans have had enough. Throughout the game, supporters chanted for Club President Ali Koc and Vice-President Acun Ilicali to resign, while manager Jose Mourinho's future also looks bleak.
Fenerbahce forked out huge money to employ Mourinho, making him one of the most well-paid managers in the world. His sole goal was to win the Super Lig.
Instead, he has been pretty pathetic. Against Galatasaray and Besiktas this season across competitions, he has zero wins, one draw and four losses. In the league, he hasn't beaten a team in the top six.
He also became the first Fenerbahce manager since Joachim Low in the 1998/99 season to lose his first two games against Besiktas.
His team plays a horrible style of football. The centre back or winger gets the ball, and they just lump it into the penalty area, hoping Dzeko or Youssef En-Nesyri might bundle it into the back of the net or win a penalty somehow.
He constantly moans and belittles the Super Lig, blaming the 'system' and this imaginary corruption instead of his own incapabilities and failures that every single person can clearly see now.
After the game, he said: "The outcome of the league was already decided before the league started. The last home losses were decisive, but the end of this league was clear before it started.
"I won't talk about Galatasaray anymore. It's very difficult to deal with this structure."
It is embarrassing. Jose Mourinho is finished at the top level and cannot wrap his head around it. He is blaming everyone but himself. He no longer handles himself with any dignity and grace.
One of football's greatest ever winners has become one of its sorest losers.
But onto Besiktas and Ole Gunnar Solskjaer, who celebrated a seismic victory at the home of Fenerbahce.
They were super impressive, and yet again, they proved they play significantly better against the tougher teams.
Ole became the first manager in Besiktas' history to win his first Super Lig matches against Fenerbahce, Galatasaray and Trabzonspor, while also becoming the first foreign coach since Mircea Lucescu in 2003 to guide Besiktas to an away win at Fenerbahce.
Interestingly, Ole was the same at Manchester United. When they sat back and hit teams on the counter-attack, his United side looked a lot better. They would often get good results against the likes of Manchester City and Liverpool, but against the rest of the Premier League, they were nowhere near as convincing.
Just in the last month and a half, they have dropped points to Goztepe, Istanbul Basaksehir, Kasimpasa, Konyaspor and Gaziantep, with a pair of wins against Fenerbahce and Galatasaray in between those.
But in this game, Ole outclassed Mourinho, setting his team up really well, and his tactical tweak of pairing Gedson and Rafa together worked a treat. Moving Masuaku to left back and bringing on Felix Uduokhai late in the game to combat Fenerbahce's crosses was also a very intelligent move.
It is an amazing result for them and keeps them firmly in the race for a top-three finish, which will be a positive from where they were when Ole was appointed.
The team needs a lot of signings, and they are still miles away from winning the title. But results against their fiercest rivals will certainly buy him some time and get the fans onside.
Galatasaray: Champions elect
Of course, Galatasaray had a job to do themselves a day earlier. Knowing there was a good chance Fenerbahce could drop points against Besiktas, they had to get the three points at home against Sivasspor.
And they did just that, soaring to a 4-1 victory. It was as comfortable a win as they have had all season, scoring all their goals in the first 30 minutes of the match.
Victor Osimhen was irresistible once more, bagging a brace to move to 24 Super Lig goals this season. With 33 goals in all competitions, it is a career high for the brilliant centre forward.
Lucas Torreira also continued his rich vein of goalscoring form with his fourth goal in his fourth straight game, while Baris Alper Yilmaz also scored with a lovely finish from outside the box.
Their last three results in all competitions read: 5-1, 5-1 and 4-1. They couldn't have found a better time to hit top form, and they are set to win a record-extending 25th league title and their third in a row.
The vibes are immaculate, and the players and fans are loving life. They face a tough trip to Trabzonspor next weekend, but due to the eight-point lead they now have at the summit, there will be significantly less pressure on that match.
A few days later, they face the same opponents in the Turkish Cup final. Galatasaray now have a great opportunity to win the domestic double, and it would be a fantastic achievement from Okan Buruk and his players.
Highlight of the week
Rizespor claimed a vital 2-0 win over Gaziantep on Saturday afternoon to ease their relegation fears, and Ali Sowe was the star of the show for his side. After having not one, but two goals ruled out for offside in the first half, Sowe finally got on the scoresheet to give his side the lead with around 15 minutes to go, and did so in style with a fabulous flicked finish into the back of the net.
Team of the week
Midfielder Ibrahim Olawoyin is the Flashscore Player of the Week, according to our very own player ratings system, after a goal and assist in Rizespor's win, with teammate Sowe also making the team.
Galatasaray duo Osimhen and Baris find a spot in the starting 11 alongside Besiktas' Paulista, while Landry Dimata is included following his brace in Samsunspor's 3-0 win over Eyupspor.
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