Ronny Deila praises Leigh Griffiths and Carlton Cole show

Carlton Cole (left) and Leigh Griffiths both scored as Celtic progressed to the Scottish Cup fifth round

Celtic manager Ronny Deila praised Leigh Griffiths and Carlton Cole as they combined to knock Stranraer out of the Scottish Cup.

Deila switched to a 4-4-2 shape to accommodate the pair as a partnership up front and they delivered an impressive display as both scored in the 3-0 win.

"Both of them scored and they have played the system before," Deila told BBC Scotland.

"It's something to build on."

Griffiths hit a double, then revealed that friends had backed him beforehand to score a hat-trick.

He was satisfied with his goals tally, although he nearly did add a third with an outstanding volley. The Scotland striker scored in each half, while Cole notched his first for the club with a header just before half-time.

"We need to have the ability to play different systems, but it's not about systems, it's about principles. We can do that with 4-4-2, 4-2-3-1, 3-5-2," said Deila.

"We controlled [the game] very well. It's tough to play away in the early rounds of the cup, and the pitch was tough as well.

"[Stranraer] started well, but we got into it after 10 minutes and then controlled the whole game. We won comfortably but should have scored more goals."

Griffiths admitted that the conditions - a strong wind and an uneven surface - made the game difficult. He enjoyed playing up front alongside Cole, though, and was impressed with the display of Stranraer's 18-year-old goalkeeper, Max Currie.

"It was good, the big man's got all the attributes I don't have," Griffiths said.

"He holds the ball up well and when there are crosses into the box, he'll put them away.

"[Currie's] double save in the first-half was outstanding. I should have put the first one away, but the second save was even better.

"If he keeps his feet on the ground, he'll have a future in the game.

"A couple of people back home said they had money on me for a hat-tick, but if you'd offered me a double beforehand, I would have taken it."

Leigh Griffiths (left) was impressed with the performance of Stranraer goalkeeper Max Currie

Stranraer manager Brian Reid was also pleased with Currie's performance, but disappointed with his side's defending for the goals they conceded.

"We knew they were going to have most of the possession, but we wanted to have a wee go," Reid said.

"The conditions were tough for both teams, but I was disappointed with the manner of the two goals we lost.

"I don't think Celtic created too much cutting us open, but we got punished when they did. Griffiths is the bane of my life, every time I play him he seems to score.

"When you've got the quality of finishers they've got, they punish you when you lose focus."