Chelsea's Champions League tie with Paris Saint-Germain always promised to be an exciting affair, and the 120-minute thriller did not disappoint.
With the game needing extra time, the two European heavyweights played out a 2-2 draw at Stamford Bridge, a result which saw the Ligue 1 champions go through on a 3-3 aggregate due to the away goals rule.
Laurent Blanc's crew have thus dumped Jose Mourinho's side out of the competition in the round of 16 and will move on to the quarter-final stage.
There were many talking points from Wednesday's encounter, ranging from Zlatan Ibrahimovic's straight red card to David Luiz scoring against his former side. However, one issue that was a hot topic on social media surrounded Diego Costa and why the striker was NOT sent off late into the second half.
The 26-year-old, during the 76th minute of the game, was guilty of committing a horrendous tackle on Les Parisiens captain Thiago Silva. Many felt the former Atletico Madrid ace's foul was worthy of a sending off, but the Spaniard escaped with just a booking.
AWFUL! Costa's tackle on Thiago Silva
That Diego Costa challenge is no better than the one Ibrahimovic receieved a red card for.
— Betfair Exchange (@BetfairExchange) March 11, 2015
Costa booked. How exactly? Has to be a red card!
— Jonathan Johnson (@Jon_LeGossip) March 11, 2015
THATS A RED CARD FOR DIEGO COSTA!!!!! HE TACKLED HIM FROM BEHIND!!!
— ⚽️Madridsta™ (@lsco_Disco) March 11, 2015
PSG furious as Diego Costa only shown yellow for flattening Thiago Silva - then David Luiz booked for shocking acting as he confronts Costa
— Phil McNulty (@philmcnulty) March 11, 2015
With the game all tied at 1-1, the more controversial incident happened shortly afterwards. Costa, after losing out and conceding a goal kick in a clash for the ball with Marquinhos, shoved the Brazilian defender to the ground in frustration.
Already on a yellow card, the Chelsea forward evaded punishment and continued on playing to see out the remainder of the game.
His shove on Marquinhos occurred just as referee Björn Kuipers turned his back on both players. Some questioned how the linesman did not spot the incident. See how Twitter reacted in the aftermath.
Twitter blasts Costa after his shove on Marquinhos
The ref might have missed Diego Costa's shove on Marquinhos, but PA snapper Andrew Matthews didn't. #CFC pic.twitter.com/hqPzYVKDDO
— PA Dugout (@PA_dugout) March 11, 2015
Referee with his back to Diego Costa as he pushes Marquinhos to the ground. Could've been sent off twice.
— Anthony Lopopolo (@sportscaddy) March 11, 2015
Diego Costa so lucky to get away with shoving Marquinhos to the floor when already on a yellow. Terrible lack of discipline.
— Phil McNulty (@philmcnulty) March 11, 2015
Diego Costa deserved a straight red after that foul when he got a yellow. Then he pushed a player like that and no yellow card was given?
— Jojo Culé. M (@jperkovic93) March 11, 2015
What Costa did to Marquinhos was a disgrace.
— Prasiddha Timilsina (@theprasiddha) March 11, 2015
Surely a red card for Costa? The Ref turned his back when he did it. What a farce of a game.
— Left Foot (@messileftfoot) March 11, 2015
And you're telling me not one of the assistant referees didn't spot Costa pushing Marquinhos to ground?
— Jay (@DoublePivot) March 11, 2015
What a moron Costa is. Why even push Marquinhos? No reason whatsover
— TheGamerCan / Curt ށ (@CurtisMorton) March 11, 2015
Someone needs to take Costa in a quiet corner and remind him two or three red card challenges a game does not make for a successful career.
— Dan Levene (@BluesChronicle) March 11, 2015
With the west London club's Champions League journey this season coming to an end, Costa, the English Premier League's top scorer, bows out of the competition without a single goal to his name.
This was something Internet trollers and anti-Chelsea fans were keen to point out, comparing him to Yaya Sanogo, who found the back of the net at least once before heading to Crystal Palace.
HUMOR: Sanogo with more goals than Costa in the UCL this season
Yaya Sanogo has scored more Champions League goals than Diego Costa this season
— Football Funnys (@FootballFunnys) March 11, 2015
This year CL goal Yaya Sanogo 1 Rickie Lambert 1 Diego Costa 0
— Nishant (@nishantafc) March 11, 2015
Champions League goals this season: Yaya Sanogo 1 appearance 1 goal Diego Costa 8 appearances 0 goals.
— Danny Welbeck (@WelBeast) March 11, 2015
Sanogo has more champs league goals than Costa 0
— Goodlife Soldier® (@PatohShanqueels) March 11, 2015 
