Chelsea moved into the fourth round of the FA Cup with a professional victory over League One side Scunthorpe United.
The hosts took an early lead when Branislav Ivanovic's right-wing cross was diverted in by Diego Costa, under pressure from two Scunthorpe defenders.
Excellent goalkeeping from Scunthorpe's Luke Daniels saw him tip over powerful efforts from Cesc Fabregas and Pedro.
But Chelsea ended the Iron's resistance when Ruben Loftus-Cheek steered in Cesar Azpilicueta's low cross for 2-0.
With Chelsea 14th in the Premier League, 19 points behind leaders Arsenal, and facing a tricky tie against Paris St-Germain in the last 16 of the Champions League, the FA Cup could represent the Blues' best chance of winning a trophy this season.
Interim boss Guus Hiddink, who lifted the FA Cup in 2009 in his last spell at the club, showed how seriously he was taking the competition with a near full-strength team against a side 45 places lower in English football's pyramid.
Chelsea lost to League One Bradford 4-2 in the fourth round of last year's competition, and, despite moving ahead on 13 minutes, had to work hard to get past a well-organised, hard-working Scunthorpe side.
The 2014-15 Premier League champions threatened to overrun their opponents as Fabregas and Pedro were denied by Daniels, with Oscar firing another chance just wide.
But Hiddink's side men did not have it all their own way as Scunthorpe ended the first half strongly, with the dangerous Luke Williams only denied by a last-ditch covering challenge from Kurt Zouma after an error from fellow centre-half Gary Cahill.
The visitors thought they had won a penalty when Kevin van Veen was clipped by Ramires but referee Craig Pawson dismissed their appeals.
However, the home side's superior quality showed as Azpilicueta got to the byeline to pull the ball back for 19-year-old midfielder Loftus-Cheek to score his first Chelsea goal and end the match as a contest.
But there was still time for Jordan Clarke to hit a 25-yard effort that was pushed on to the post by Blues goalkeeper Asmir Begovic.
Chelsea manager Guus Hiddink, who says Costa is "doubtful" for the Blues' Premier League game against West Brom on Wednesday, says: "I was happy with the result. The Premier League is difficult to get the fourth place, but the other projects are the FA Cup and the Champions League
"It is a decent result against a very strong opponent, especially in their set-pieces. We started well, but we forgot to kill it off.
"We had high pressing, but we were a little bit arrogant in our finishing."
Asked if he was tempted to make more changes to his starting line-up, he replied: "The temptation was there, but the will was to not have the same experience as last year when they were kicked out in the early stages."
Scunthorpe United boss Mark Robins was frustrated by the decision to not give his side a penalty when Van Veen was fouled by Ramires.
He said: "Chelsea made it very difficult for us and early on we gave the ball away too much but after that I thought we were good.
"It is a nailed-on penalty and you come to places like this and you want to get the decisions, but sometimes you don't
"We had opportunities to score but unfortunately Loftus-Cheek managed to get into the penalty area and made a decent contact on it for 2-0."
Chelsea are back in action on Wednesday as West Brom visit Stamford Bridge in a Premier League game, but Scunthorpe get some time to rest as they next play on Saturday - a League One match at Blackpool.
Full Time Match ends, Chelsea 2, Scunthorpe United 0.
90:00 +3:11 Full timeFull Time Second Half ends, Chelsea 2, Scunthorpe United 0.
90:00 +3:06Attempt missed. Neal Bishop (Scunthorpe United) left footed shot from the centre of the box is close, but misses to the left following a corner.
90:00 +2:47Corner, Scunthorpe United. Conceded by Bertrand Traore.
90:00 +2:19Corner, Scunthorpe United. Conceded by Kurt Zouma.
90:00 +0:18Hand ball by Scott Laird (Scunthorpe United).
88:42Foul by Bertrand Traore (Chelsea).
88:42Murray Wallace (Scunthorpe United) wins a free kick in the defensive half.
86:10Corner, Scunthorpe United. Conceded by Asmir Begovic.
86:07Attempt saved. Jordan Clarke (Scunthorpe United) right footed shot from the right side of the box is saved in the top right corner. Assisted by Paddy Madden.
85:58Attempt blocked. Neal Bishop (Scunthorpe United) right footed shot from outside the box is blocked.
85:11 SubstitutionSubstitution Substitution, Chelsea. Bertrand Traore replaces Diego Costa.
83:25Ramires (Chelsea) wins a free kick in the attacking half.
83:25Foul by Scott Laird (Scunthorpe United).
82:24Kenedy (Chelsea) wins a free kick in the attacking half.
82:24Foul by Jamie Ness (Scunthorpe United).
80:52 SubstitutionSubstitution Substitution, Scunthorpe United. Kyle Wootton replaces Kevin van Veen.
78:42 SubstitutionSubstitution Substitution, Scunthorpe United. Jack King replaces Stephen Dawson.
78:31 SubstitutionSubstitution Substitution, Scunthorpe United. Hakeeb Adelakun replaces Luke Williams.
77:47Attempt missed. Paddy Madden (Scunthorpe United) right footed shot from outside the box is too high. Assisted by Scott Laird.
Willian (Chelsea) wins a free kick in the attacking half.
74:58Foul by Murray Wallace (Scunthorpe United).
73:48Kurt Zouma (Chelsea) wins a free kick in the defensive half.
73:48Foul by Paddy Madden (Scunthorpe United).
72:23Attempt missed. Kevin van Veen (Scunthorpe United) right footed shot from long range on the left is close, but misses to the left from a direct free kick.
71:36Foul by Kurt Zouma (Chelsea).
71:36Stephen Dawson (Scunthorpe United) wins a free kick on the left wing.
71:03 SubstitutionSubstitution Substitution, Chelsea. Kenedy replaces Pedro.
70:45Foul by Ruben Loftus-Cheek (Chelsea).
70:45Neal Bishop (Scunthorpe United) wins a free kick in the defensive half.
69:59Attempt blocked. Luke Williams (Scunthorpe United) right footed shot from outside the box is blocked. Assisted by Jordan Clarke.
67:59 Goal scoredGoal! Goal! Chelsea 2, Scunthorpe United 0. Ruben Loftus-Cheek (Chelsea) left footed shot from the centre of the box to the bottom left corner. Assisted by César Azpilicueta with a cross.
65:44Foul by Pedro (Chelsea).
65:44Stephen Dawson (Scunthorpe United) wins a free kick in the attacking half.
65:13 BookingBooking Branislav Ivanovic (Chelsea) is shown the yellow card.
64:17Offside, Scunthorpe United. Scott Laird tries a through ball, but Stephen Dawson is caught offside.
63:26Attempt missed. Ramires (Chelsea) right footed shot from outside the box misses to the left.
62:30 BookingBooking Stephen Dawson (Scunthorpe United) is shown the yellow card.
62:15Willian (Chelsea) wins a free kick in the defensive half.
62:15Foul by Kevin van Veen (Scunthorpe United).
60:56Diego Costa (Chelsea) wins a free kick in the defensive half.
60:56Foul by Neal Bishop (Scunthorpe United).
58:23Ruben Loftus-Cheek (Chelsea) wins a free kick in the defensive half.
58:23Foul by Neal Bishop (Scunthorpe United).
50:00Diego Costa (Chelsea) wins a free kick on the left wing.
50:00Foul by Jordan Clarke (Scunthorpe United).
47:40Foul by Ruben Loftus-Cheek (Chelsea).
47:40Neal Bishop (Scunthorpe United) wins a free kick in the defensive half.
45:00Second Half begins Chelsea 1, Scunthorpe United 0.
45:00 SubstitutionSubstitution Substitution, Chelsea. Ruben Loftus-Cheek replaces Oscar.
45:00 +1:06 Half timeHalf Time First Half ends, Chelsea 1, Scunthorpe United 0.
43:39Corner, Scunthorpe United. Conceded by Kurt Zouma.
41:39Foul by Branislav Ivanovic (Chelsea).
41:39Luke Williams (Scunthorpe United) wins a free kick on the left wing.
40:33Foul by César Azpilicueta (Chelsea).
40:33Paddy Madden (Scunthorpe United) wins a free kick in the attacking half.
39:01Attempt missed. Willian (Chelsea) right footed shot from outside the box is close, but misses the top right corner. Assisted by Diego Costa.
37:28Corner, Scunthorpe United. Conceded by Cesc Fàbregas.
36:51Attempt missed. Pedro (Chelsea) right footed shot from the centre of the box is close, but misses to the left. Assisted by Branislav Ivanovic with a cross.
33:15Attempt saved. Luke Williams (Scunthorpe United) right footed shot from outside the box is saved in the bottom right corner. Assisted by Scott Laird.
32:28Corner, Scunthorpe United. Conceded by Kurt Zouma.
31:44Foul by Pedro (Chelsea).
31:44Kevin van Veen (Scunthorpe United) wins a free kick in the attacking half.
31:19Corner, Chelsea. Conceded by Jordan Clarke.
30:45Corner, Chelsea. Conceded by Murray Wallace.
29:49Cesc Fàbregas (Chelsea) wins a free kick in the attacking half.
29:49Foul by Neal Bishop (Scunthorpe United).
25:53Attempt blocked. Stephen Dawson (Scunthorpe United) right footed shot from outside the box is blocked.
25:49Attempt missed. Kevin van Veen (Scunthorpe United) left footed shot from the centre of the box misses to the left following a corner.
25:05Corner, Scunthorpe United. Conceded by Gary Cahill.
21:59Attempt missed. Oscar (Chelsea) right footed shot from the centre of the box is close, but misses to the right. Assisted by Diego Costa.
20:17Corner, Chelsea. Conceded by Luke Daniels.
20:15Attempt saved. Pedro (Chelsea) right footed shot from the right side of the box is saved in the top centre of the goal. Assisted by Cesc Fàbregas with a through ball.
15:34Corner, Chelsea. Conceded by Luke Daniels.
15:32Attempt saved. Cesc Fàbregas (Chelsea) right footed shot from outside the box is saved in the top centre of the goal.
13:37Ramires (Chelsea) wins a free kick in the attacking half.
13:37Foul by Kevin van Veen (Scunthorpe United).
12:20 Goal scoredGoal! Goal! Chelsea 1, Scunthorpe United 0. Diego Costa (Chelsea) left footed shot from the centre of the box to the bottom left corner. Assisted by Branislav Ivanovic with a cross.
10:58Pedro (Chelsea) wins a free kick on the left wing.
10:58Foul by Stephen Dawson (Scunthorpe United).
10:08Branislav Ivanovic (Chelsea) wins a free kick in the defensive half.
10:08Foul by Kevin van Veen (Scunthorpe United).
1:31Attempt blocked. Luke Williams (Scunthorpe United) right footed shot from outside the box is blocked.
0:00First Half begins.
0:00Lineups are announced and players are warming up.
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