text: Bertrand Traore, playing as a central striker, gave the Blues the lead when he took Nemanja Matic's pass, turned and fired home from 20 yards out.
  The Potters deservedly levelled when Xherdan Shaqiri's cross was punched by Chelsea keeper Thibaut Courtois to Diouf, who headed into an empty net.
  Bojan almost won it for the Potters in injury time but Courtois denied him.
  Stoke remain seventh in the table, with Chelsea 10th - three points behind them.
  The Blues named a team with Wednesday's Champions League game against Paris St-Germain in mind. Striker Diego Costa, who had a minor tendon injury, was not risked, while midfielder Cesc Fabregas was left on the bench.
  Burkina Faso forward Traore started centrally, with recognised strikers Loic Remy and Alexandre Pato on the bench, and his goal was the one real moment of quality in the game.
  He found space outside the box before firing a great shot past Jack Butland - his fourth goal in five games.
  However, he had a mixed game, failing to control the ball in the box on a couple of occasions and being caught offside needlessly.
  He was replaced after 68 minutes by Remy, who made little impact.
  Chelsea could have had a penalty when Marc Muniesa leaned on Oscar in the box but there were only muted appeals for a spot-kick.
  The Potters had won their previous three Premier League games and started the day five points off the Champions League places.
  Mark Hughes named an attacking line-up at the home of the soon-to-be dethroned champions, with Ibrahim Afellay, Shaqiri and Marko Arnautovic starting behind Diouf. When Bojan replaced Glenn Whelan, they had five forwards on the pitch.
  And just when it looked like their luck might be out - Courtois had done well to deny Shaqiri and Arnautovic - they got their reward.
  With Joselu waiting on the touchline to replace Diouf, the Senegal striker headed home after Courtois failed to adequately deal with Shaqiri's cross. That was his last touch.
  Hughes told BBC Sport: "That's the bit of luck you need. He put a great shift in. He was looking a bit tired so I thought I'd freshen it up. Luckily he scored just before I brought him off."
  Stoke boss Mark Hughes told BBC Sport: "We're grateful to equalise but we deserved more from the game. It was an excellent away performance - we took the game to Chelsea. We were encouraged by the team they picked.
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  "I was a bit surprised with their team. I thought they had a chance to get in the Champions League.
  "We're really pleased with the performance. Their goal came out of the blue, it was a great bit of individual skill. I felt we were a strong team and made things happen."
  Chelsea interim boss Guus Hiddink told BBC Sport: "Stoke play well and creatively and they pushed us back. The first goal we got after a sloppy start, it was a beautiful goal.
  "We should have got a penalty for a foul on Oscar. Any referee would have given a free-kick if it was outside the box. That was a key point. Stoke got some encouragement after that.
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  "We have rested one or two players but it's good to see the players who came in, especially the young ones, like Traore and Ruben Loftus-Cheek, do well.
  "Everyone knows in December we were one point off the relegation zone. There was a little bit of panic. Through a lot of draws at the beginning, we moved away and then we had to make the next step with victories, which we did."
  Chelsea's next two games will have more of an impact on their chances of winning a trophy than the Stoke fixture.
  On Wednesday, they try to overhaul a 2-1 first-leg deficit against PSG in the Champions League last 16, while next Saturday they go to Everton in the FA Cup quarter-finals.
  Stoke's next game is at home to Southampton next Saturday.
  Match ends, Chelsea 1, Stoke City 1.
  Second Half ends, Chelsea 1, Stoke City 1.
  Attempt missed. Gary Cahill (Chelsea) header from the centre of the box is just a bit too high. Assisted by Willian with a cross following a corner.
  Corner,  Chelsea. Conceded by Erik Pieters.
  Attempt saved. Bojan (Stoke City) right footed shot from the centre of the box is saved in the centre of the goal. Assisted by Giannelli Imbula.
  Attempt blocked. Joselu (Stoke City) right footed shot from outside the box is blocked. Assisted by Bojan.
  Substitution, Stoke City. Stephen Ireland replaces Marko Arnautovic.
  Attempt missed. Oscar (Chelsea) header from the left side of the six yard box is just a bit too high. Assisted by Willian with a cross following a corner.
  Corner,  Chelsea. Conceded by Jack Butland.
  Attempt saved. Baba Rahman (Chelsea) left footed shot from outside the box is saved in the bottom left corner. Assisted by Loïc Remy.
  Giannelli Imbula (Stoke City) wins a free kick in the defensive half.
  Foul by John Obi Mikel (Chelsea).
  Substitution, Stoke City. Joselu replaces Mame Biram Diouf.
  Goal!  Chelsea 1, Stoke City 1. Mame Biram Diouf (Stoke City) header from the centre of the box to the high centre of the goal.
  Substitution, Chelsea. Cesc Fàbregas replaces Nemanja Matic.
  Bojan (Stoke City) wins a free kick in the defensive half.
  Foul by Nemanja Matic (Chelsea).
  Attempt saved. Ruben Loftus-Cheek (Chelsea) right footed shot from a difficult angle on the left is saved in the centre of the goal. Assisted by Willian with a through ball.
  Foul by Erik Pieters (Stoke City).
  Oscar (Chelsea) wins a free kick on the right wing.
  Offside, Chelsea. Nemanja Matic tries a through ball, but Loïc Remy is caught offside.
  Hand ball by Bojan (Stoke City).
  Substitution, Stoke City. Bojan replaces Glenn Whelan.
  Attempt missed. Willian (Chelsea) right footed shot from outside the box is close, but misses to the right from a direct free kick.
  Glenn Whelan (Stoke City) is shown the yellow card for a bad foul.
  Foul by Glenn Whelan (Stoke City).
  Ruben Loftus-Cheek (Chelsea) wins a free kick in the attacking half.
  Attempt blocked. Marko Arnautovic (Stoke City) right footed shot from the left side of the box is blocked. Assisted by Philipp Wollscheid.
  Corner,  Stoke City. Conceded by Branislav Ivanovic.
  Substitution, Chelsea. Loïc Remy replaces Bertrand Traore.
  Ibrahim Afellay (Stoke City) wins a free kick on the left wing.
  Foul by John Obi Mikel (Chelsea).
  Foul by Xherdan Shaqiri (Stoke City).
  Willian (Chelsea) wins a free kick in the defensive half.
  Foul by Marc Muniesa (Stoke City).
  Bertrand Traore (Chelsea) wins a free kick on the right wing.
  Attempt blocked. Ruben Loftus-Cheek (Chelsea) right footed shot from outside the box is blocked.
  Foul by Giannelli Imbula (Stoke City).
  Willian (Chelsea) wins a free kick on the left wing.
  Attempt blocked. Geoff Cameron (Stoke City) left footed shot from the right side of the box is blocked. Assisted by Glenn Whelan.
target: Mame Biram Diouf scored a late equaliser as Stoke prevented Chelsea from overtaking them in the league.