Roy Keane believes Carlos Edwards may have been his most important signing in the January transfer window because he provides the perfect balance to the Black Cats midfield.
When the 28-year-old joined from Luton Town for £1.4m last month he became the only specialist right-winger in the Wearsiders' squad.
Edwards' predecessor in the number seven shirt, Liam Lawrence, was unceremoniously forced out of the Stadium of Light in November after an argument with his manager. The Midlander joined Stoke City initially on a pre-transfer window loan before making the deal permanent in the New Year.
Tommy Miller, Stephen Elliott, Dean Whitehead, Daryl Murphy and Liam Miller have also played on the right flank there for Sunderland this season. But Keane believes he's finally got the right man for the job now in Edwards.
"Carlos gives a balance to the team because of the position he plays," said the Black Cats boss. "After Liam Lawrence left - and even when I first got the job - we were trying a lot of different players out there.
"Liam Miller and Stephen Elliott played there a bit but, while that's fine in the short-term if you need to adapt, it's not a long-term solution. We needed somebody who naturally went wide when we had the ball. He gives us that natural width, like Toby (Hysen) and Ross (Wallace) do on the other side.
"Carlos gives us that and it's natural for him to run with the ball at his feet. He gives us a bit of width, and he's a threat because he scores the odd goal as well. That's a real bonus."
Since making his full debut in the 1-0 win at home to Ipswich Town, Edwards has played in all four games, scoring against Sheffield Wednesday and Coventry City.
Keane has also expressed his delight at the way Edwards has lived up to the billing he was given before transferring to the Wearsiders.
"We made enquiries before we bought him and everyone came back and said, `He works well and he's a team player'," said Keane. "You could see that at Wrexham and Luton. He's worked hard throughout his career.
"He's great in training and he's great on the pitch. I don't hear too much of him, he just gets on with his work and he's no trouble at all. We hope he's going to make a big contribution, not just in terms of this season but also over the next few years."
With Edwards being one of the few positions not well covered by Sunderland's extensive squad, a long-term injury to him would arguably be more damaging than to almost any other Black Cats player. Keane, though, insists he does not allow himself such thoughts.
"I don't over-worry about any of the players in that state," he said. "If they get injured they get injured.
"These things happen so I don't get over worried, we've got good players challenging to come in. It's not ideal but I don't lose any sleep over it."
Edwards was denied what Keane saw as a "blatant" penalty in the last minute of Saturday's 2-0 win over Coventry City and, despite his sense of injustice, the Irishman will not encourage his players to exaggerate contact in the box.
"That's 63 games without a penalty now," he said. "I wouldn't know who would have taken it had we got one on Saturday. There's no point practising them.
"I'd never say go down to a player, never, a lot of that comes from abroad with coaching or perhaps that's their mentality. People tell me that come the end of the season, then things even themselves out.
"Hopefully we might be given some before the end of the season."