Rangers manager Philippe Clement tells BBC Scotland: "It's a really important win, we were never in trouble. These are always tricky games on a pitch like this.
"We did the job in a good way. It's now about a good recovery towards Wednesday. The most satisfying thing was I could rotate.
On Fabio Silva: "He's come here for football. He's hungry. He's been in England so he's used to the rain, don't worry."
Clement adds he expects more incomings in this window.
SNSCopyright: SNS
When's the draw?
Again, you'll catch that on Sportscene - but tomorrow night's.
That's on the BBC Scotland channel at 19:15 GMT on Sunday.
Sportscene to come
You'll be able to catch the best of the fourth round action on Sportscene tonight.
It all kicks off at 22:30 GMT on BBC One Scotland.
'There's always been hunger' - Lundstram
FT: Dumbarton 1-4 Rangers
Rangers midfielder John Lundstram tells Viaplay: "There were some sloppy bits. This could have been a real upset on another night. The boys were spot on.
"I maybe need to be a bit more selfish when I get to on the edge of the box. Goals are something I want to add to my game.
"There's always been a hunger in the squad, we just haven't quite got it right over the years."
SNSCopyright: SNS
The last-16 line-up so far
Scottish Cup
Aberdeen
Hearts
Airdrieonians
Ayr Utd
Bonnyrigg Rose
Hibernian
Greenock Morton
Inverness CT
Kilmarnock
Livingston
Motherwell
Partick Thistle
St Mirren
Rangers
Cove or Brora Rangers
Celtic or Buckie Thistle
FULL-TIME
Dumbarton 1-4 Rangers
Comfortable enough in the end for four-goal Rangers in awful conditions at The Rock.
Into the last 16 Philippe Clement's side go.
SNSCopyright: SNS
Post update
Dumbarton 1-4 Rangers
Into stoppage now as Rangers keep the ball moving.
'That's that'
Dumbarton 1-4 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
Just when you thought Dumbarton had a bit of a lifeline...
Scott Wright hits it low, brilliant power. That's that.
GOAL! Dumbarton 1-4 Rangers
Scott Wright
Spoiler: there will be no twist.
Scott Wright leathers one from the edge of the box and it skims underneath the keeper.
'Twist incoming?'
Dumbarton 1-3 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
Matthew Shiels just had to make contact and guide it in.
It's a brilliant ball in. Is there a twist in the tale?
GOAL! Dumbarton 1-3 Rangers
Matthew Shiels
Hello.
It's almost certainly too late, but Matthew Shiels flicks a lovely header into the far post for Dumbarton.
CLOSE!
Dumbarton 0-3 Rangers
Fabio Silva dances his way into the Dumbarton box before reversing a finish just wide.
That would've been a lovely goal.
'Exquisite'
Dumbarton 0-3 Rangers
Jim Duffy
Ex-Dumbarton manager on BBC Sportsound
An exquisite penalty from Tavernier. People think it's easy. Firm side foot, into the side net, keeper no chance.
Rangers have deserved to be 3-0 victors, but Dumbarton deserve a lot of credit.
'Perfect pen'
Dumbarton 0-3 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
He slots it away perfectly, generates all the power with the inside of his foot.
The ref had no option there.
GOAL! Dumbarton 0-3 Rangers
James Tavernier (pen)
The Rangers captain smashes in to the right-hand corner.
PENALTY to Rangers!
Dumbarton 0-2 Rangers
Rabbi Matondo goes down under a challenge and the referee points to the spot.
Looks a pen through the rain-soaked camera lens.
'Credit to Dumbarton'
Dumbarton 0-2 Rangers
Jim Duffy
Ex-Dumbarton manager on BBC Sportsound
You have to give great credit to the way Dumbarton have defended.
They've given everything for their manager, they've been resolute, and they still keep putting bodies in the right place. The keeper hasn't had a save to make second half.
Post update
Dumbarton 0-2 Rangers
Fabio Silva looks to break through the Dumbarton defence but he's squeezed out of possession.
Post update
Dumbarton 0-2 Rangers
Reckon both these teams would shake on this now if they could.
Live Reporting
Nick McPheat
All times stated are UK
SNSCopyright: SNS 
SNSCopyright: SNS -
Aberdeen
-
Hearts
-
Airdrieonians
-
Ayr Utd
-
Bonnyrigg Rose
-
Hibernian
-
Greenock Morton
-
Inverness CT
-
Kilmarnock
-
Livingston
-
Motherwell
-
Partick Thistle
-
St Mirren
-
Rangers
-
Cove or Brora Rangers
-
Celtic or Buckie Thistle
SNSCopyright: SNS 
Latest PostG'night
That'll do us, folks.
Thanks for joining on a long but eventful day.
We'll be back tomorrow, cheerio.
'Really important win in tricky conditions'
FT: DUmbarton 1-4 Rangers
Rangers manager Philippe Clement tells BBC Scotland: "It's a really important win, we were never in trouble. These are always tricky games on a pitch like this.
"We did the job in a good way. It's now about a good recovery towards Wednesday. The most satisfying thing was I could rotate.
On Fabio Silva: "He's come here for football. He's hungry. He's been in England so he's used to the rain, don't worry."
Clement adds he expects more incomings in this window.
When's the draw?
Again, you'll catch that on Sportscene - but tomorrow night's.
That's on the BBC Scotland channel at 19:15 GMT on Sunday.
Sportscene to come
You'll be able to catch the best of the fourth round action on Sportscene tonight.
It all kicks off at 22:30 GMT on BBC One Scotland.
'There's always been hunger' - Lundstram
FT: Dumbarton 1-4 Rangers
Rangers midfielder John Lundstram tells Viaplay: "There were some sloppy bits. This could have been a real upset on another night. The boys were spot on.
"I maybe need to be a bit more selfish when I get to on the edge of the box. Goals are something I want to add to my game.
"There's always been a hunger in the squad, we just haven't quite got it right over the years."
The last-16 line-up so far
Scottish Cup
FULL-TIME
Dumbarton 1-4 Rangers
Comfortable enough in the end for four-goal Rangers in awful conditions at The Rock.
Into the last 16 Philippe Clement's side go.
Post update
Dumbarton 1-4 Rangers
Into stoppage now as Rangers keep the ball moving.
'That's that'
Dumbarton 1-4 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
Just when you thought Dumbarton had a bit of a lifeline...
Scott Wright hits it low, brilliant power. That's that.
GOAL! Dumbarton 1-4 Rangers
Scott Wright
Spoiler: there will be no twist.
Scott Wright leathers one from the edge of the box and it skims underneath the keeper.
'Twist incoming?'
Dumbarton 1-3 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
Matthew Shiels just had to make contact and guide it in.
It's a brilliant ball in. Is there a twist in the tale?
GOAL! Dumbarton 1-3 Rangers
Matthew Shiels
Hello.
It's almost certainly too late, but Matthew Shiels flicks a lovely header into the far post for Dumbarton.
CLOSE!
Dumbarton 0-3 Rangers
Fabio Silva dances his way into the Dumbarton box before reversing a finish just wide.
That would've been a lovely goal.
'Exquisite'
Dumbarton 0-3 Rangers
Jim Duffy
Ex-Dumbarton manager on BBC Sportsound
An exquisite penalty from Tavernier. People think it's easy. Firm side foot, into the side net, keeper no chance.
Rangers have deserved to be 3-0 victors, but Dumbarton deserve a lot of credit.
'Perfect pen'
Dumbarton 0-3 Rangers
Stephen Craigan
Former Motherwell captain on Viaplay
He slots it away perfectly, generates all the power with the inside of his foot.
The ref had no option there.
GOAL! Dumbarton 0-3 Rangers
James Tavernier (pen)
The Rangers captain smashes in to the right-hand corner.
PENALTY to Rangers!
Dumbarton 0-2 Rangers
Rabbi Matondo goes down under a challenge and the referee points to the spot.
Looks a pen through the rain-soaked camera lens.
'Credit to Dumbarton'
Dumbarton 0-2 Rangers
Jim Duffy
Ex-Dumbarton manager on BBC Sportsound
You have to give great credit to the way Dumbarton have defended.
They've given everything for their manager, they've been resolute, and they still keep putting bodies in the right place. The keeper hasn't had a save to make second half.
Post update
Dumbarton 0-2 Rangers
Fabio Silva looks to break through the Dumbarton defence but he's squeezed out of possession.
Post update
Dumbarton 0-2 Rangers
Reckon both these teams would shake on this now if they could.