Phillips has missed the last three league games with a muscle strain after being forced off during the 2-0 win over Millwall last month.
Free agent Sako was signed last week after impressing on trial but was not named in the first two squads he was eligible for because of fitness concerns.
However, Albion are confident both will be up to speed by the time they travel to the DW Stadium a week on Saturday.
Sako has been training with Albion for almost a month, but he hasn’t played a senior competitive fixture since January, and is expected to be gradually introduced to the squad.
He is unlikely to make the starting XI at Wigan, but with three games in eight days, could feature in the first week back.
Phillips, however, is likely to return to the starting line-up at right wing-back following his blistering start to the season.
“Matty’s been different class,” said Moore, before the international break. “He’s been superb.
“He’s a very attacking player, very strong, got bags of quality, scores goals and assists.
“In terms of his creativity, Matty’s been superb and hopefully he’s enjoying his football.”
Phillips has impressed at wing-back since Moore switched to his successful 3-4-1-2 system, scoring four goals from nine league appearances.
“He’s shown his versatility,” said Moore. “He’s adapting, whilst keeping his creativity and his goalscoring prowess.
“He understands the dynamics of the team as well, what we deem the ugly part of the game, off the ball.
“You’ve seen in recent weeks he’s done that and hopefully continues to do that.”
Phillips endured a poor season in the Premier League last term, but his form turned around when Moore was made caretaker manager.
And the Baggies boss believes the 27-year-old is still improving each week.
“Areas of his game are getting better,” he said. “In possession of the ball he’ll say he’s getting better.
“Off the ball he’s doing really well and he’s playing a big part for the team so long may that continue over the weeks and months ahead.”