DAVE Artell said he believes Crewe are still capable of staying in League One despite another chastening defeat.

While the Alex were improved on Saturday's showing at Fleetwood and offered Lee Johnson's high fliers a taxing opening 20 minutes the scoreline doesn't reflect kindly on those early efforts.

But it didn't flatter the Wearsiders who could easily have added one or two more to their tally as Crewe were stretched in the closing stages.

As it was a promising opening faded after Terell Thomas sliced a cruel own goal past Will Jaaskelainen (25) and Ross Stewart doubled the lead before the break (32).

A Crewe side showing four changes from the weekend advanced with intent at times, but lacked quality in the final third. They have scored only nine times in 13 games and it is not hard to see why even with changes up top with Mikael Mandron and Chris Long drafted in.

But it was the creaking backline which mainly contributed to this heavy defeat with Artell lashing into his players for failing to defend set pieces.

Asked whether he believed Crewe could pull themselves clear of the drop zone, the Crewe boss stressed: "I have seen enough certainly. Am I concerned? Well the table doesn't lie and it is down to us.

"We have been working hard on improving and we will improve. We have got to make sure that everyone at this club, including the staff and the fans are all heading in the right direction and we don't give up."

And the Alex manager added: "We have got to be harder to beat, which we were earlier in the season.

"We've conceded from two set-pieces and that's five goals [from set pieces] in the last three games – that makes it impossible.

"Early on I thought we were the better team and we were forcing them into mistakes. But we didn't recover well from the own goal and the third goal killed us."

Without a win now in seven games Crewe are in danger of getting cast adrift in the bottom four if they don't squeeze results out of a difficult trip to Wycombe on Saturday followed by a visit from sixth-placed MK Dons the week after.

They were indebted to Will Jaaskelainen early on as the keeper was at full stretch palming over Tom Flanagan's header from a corner and then beating an effort out from Alex Pritchard.

Long may have done better when an opening presented itself 30 yards out after J'Neil Bennett pinched possession. But the former Motherwell attacker, making his first League One start for the Alex, took far too long getting his shot away and the low effort was easily fielded by Ron Hoffman.

During a prolonged spell of pressure Crewe did pin the lofty visitors back and Scott Robertson drove a yard wide from distance before Kane Ramsay swiped an effort past the top corner.

Yet despite drafting in Donervon Daniels into a back three, Crewe looked anything but secure when Sunderland advanced. They were fortunate that Aiden O'Brien's control let him down as he took down a high ball alone in the box.

Then Thomas rather unfortunately sliced Pritchard's cross past Jaaskelainen and into the far corner of his own net for the Black Cats' 25th-minute opener.

But there was no luck about the visitors' second as Dan Neil was worked clear to hang a cross from the byline onto the head of Ross Stewart, who found the far corner (32).

There could have been more for Johnson's side before the half closed with O'Brien lofting over as he met Aiden McGeady's delivery at the far post.

The third duly arrived in the 55th-minute as Crewe crumbled at a Pritchard corner with Callum Doyle's flick allowing Stewart an easy finish for his second of the night.

Mandron was agonisingly close to finding the far corner with an unorthodox effort, but Hoffman's long reach turned the ball around the post.

Scott Kashket and Madger Gomes were on by the hour mark and Gomes managed to bludgeon an effort over at the end of some set-piece pressure.

But it was short-lived resistance and soon Sunderland were making the most of the gaping room on the counter to rub in the misery. Sub Leon Dajaku took Neil's pass and galloped clear on the right to shoot under Jaaskelainen for the fourth (73).

Wearsiders' boss Lee Johnson said: "Crewe were plucky and we probably scored against the run of play [for the opener]. But our counter attacking was really slick and we had a few gears in us.

"Crewe are a good team and caused problems in the first 15 minutes. Their press was really good and once we worked that out we did most of the damage in the first half."

Crewe: Jaaskelainen; Offord, Thomas (Sass-Davies), Daniels; Ramsay, Murphy, Robertson, McFadzean; Long (Gomes), Mandron, Bennett (Kashket).

Subs: Burge, Younger, Harris, Wearne.