Neil Lennon was pleased to see his Celtic side keep a clean sheet in the 3-0 away league win against St Johnstone. Niall McGinn double helped take Celtic level on points with Scottish Premier League leaders Rangers.
McGinn had the visitors ahead with just over a minute gone and four minutes from the end of a one-side half Emilio Izaguirre grabbed the second.
"We've conceded five in the previous two games, so it was something we needed to concentrate on," said Lennon.
"The back four gave us a platform to go and win the game.
"All of them were superb, particularly Thomas Rogne, considering he's been out for a long time. He did well and the full-backs were excellent too."
"I'm not trying to send a message to anyone," said Lennon. "He (Loovens) probably hasn't done himself justice of late, and he's got competition.
"So we decided to change things round a bit, and Thomas came in and took his chance.
"We were delighted to get off to a good start - it gave us a platform to go and play in the second half, and if we had been a bit more clinical in front of goal, we could have won it a bit more comfortably."