Alex rescued Paris St Germain from a second defeat in three days as the Brazilian defender's late goal earned a 1-1 draw at Guingamp.
The Ligue 1 leaders were knocked out of the Coupe de France by Montpellier in midweek, and another loss looked to be on the cards on Saturday when they fell behind to a Mustapha Yatabare strike in the 84th minute.
However, former Chelsea man Alex struck four minutes later to secure a result which takes PSG to six matches unbeaten in the league.
PSG had something of a point to prove after their cup exit and Zlatan Ibrahimovic fired inches over the bar after 10 minutes at Stade du Roudourou.
Guingamp were not to be outdone, though, and responded with a 30-yard volley from Rachid Alioui which beat goalkeeper Salvatore Sirigu but also the right post.
Ibrahimovic tried his luck once more as the interval approached, also with a shot on the volley which brought a good save out of home goalkeeper Guy N'Dy Assembe.
But it was Guingamp who came closest to breaking the deadlock in the first half, with Sirigu deflecting an Alioui free-kick on to the crossbar with his foot before it fell safely behind.
PSG looked some way short of their best and N'Dy Assembe was once more a cause of frustration for Ibrahimovic seven minutes after the interval, with the Swedish star's shot kept out at point-blank range.
Alex then came to the rescue at the other end, heading Thibault Giresse's fierce strike off the line as Guingamp looked to edge ahead.
And edge ahead they did after 83 minutes when Alioui's corner was turned in by Yatabare.
It seemed PSG were heading for another defeat but Alex came to the fore with minutes remaining, tucking a low shot under N'Dy Assembe who had come too far off his line to meet a corner from Lucas.