GOALKEEPER Mart Poom has put Sunderland's recent revival down to improvements in Mick McCarthy's backline.

After a shaky start to the season, when the Black Cats won just one of their opening six fixtures, Steve Caldwell and Gary Breen have been instrumental in an upturn in fortunes.

Sunderland have won their last three Championship matches and kept two clean sheets against Nottingham Forest and Gillingham.

Poom, knowing Caldwell is due to return tonight to Leeds, where he spent a spell on loan last season, said: "Defenders and keepers have to work as a unit and we are doing that now. If they have good understanding then it helps the rest of the team.

"I didn't know much about Steve when he first came but it will be a big game for him. He was at Newcastle before that but all I care about is that Gary and Steve are beginning to look good together."

Manager McCarthy agrees that the pair's displays have been the major factor in the club's turnaround in fortunes.

"They have been fundamental to our success recently. They didn't start well together in pre-season but it is a partnership that is growing," said McCarthy.

"If the two work together and can be formidable then that's fantastic for us. If we have that foundation to build on then we can play. But if we keep leaking goals it's going to be a problem.

"It can take time. They need to get that understanding. It becomes second nature eventually."

Poom is desperate to see Sunderland continue their recent good form and close the five-point gap between themselves and early leaders Wigan.

"We have won the last three and are moving in the right direction. We want automatic promotion but there are a lot of teams in that sort of position," said Poom, who will travel with Sunderland to face Sheffield United on Tuesday.

"Wigan are doing really well and have not lost a game. But we have the same aims and we have a chance but it will be tight between now and the end of the season. It's not like the Premier League. Any team can beat anybody on the day. It's a much more even league and much harder."

Sunderland's goalkeeping coach Tim Carter has been given a new role on the Estonian national team's coaching staff - after being recommended by Poom.

And the 36-year-old has been given the go-ahead to continue in both roles as he looks to help Estonia reach the World Cup 2006.

"The job covers the qualifying games and I'll travel with the squad and work with the keepers. Hopefully it will help Sunderland as well in that I'll become a better coach from the international experience."

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