The Celtics faced the Atlanta Hawks on Friday night, seeking their eighth straight win, missing only Al Horford and Guerschon Yabusele.

BOSTON – The once-crowded Celtics’ injury list has been reduced to just two players.

After missing five players for one game this week and four players for another, the Celtics were minus only Al Horford and Guerschon Yabusele on Friday night when they faced the Atlanta Hawks at the TD Garden.

Gordon Hayward and Jaylen Brown returned after both had been ill, giving the Celtics 12 active players as they went for an eighth straight victory.

The Celtics played Monday night’s game against the New Orleans Pelicans with just 10 players, including P.J. Dozier, who had been recalled that morning from the Maine Red Claws.

With all the absences during the week, coach Brad Stevens used rookie Robert Williams and guard Brad Wanamaker in the rotation with Semi Ojeleye’s minutes also increasing.

“I guess it’s always beneficial,’’ said Stevens. “I’d like to see our whole group, but obviously it’s going to be at least a few games. But in the meantime, next guy steps up and we’re going to give all those guys an opportunity to play.’’

Williams, who appeared in only nine of the Celtics’ first 25 games this season, had 11 rebounds, seven points and three blocks in the win over the Pelicans and six points, six rebounds and two blocks in an overtime win over the Washington Wizards.

“Just keeping that next man up mentality,’’ said Williams before going against the Hawks. “Just focusing on doing what they ask me to do.’’

Williams said he has been leaning heavily on the veterans for advice as his first season goes on.

“They’re the No. 1 resource,’’ said Williams. “Obviously they’ve been through it all. It’s mandatory.’’

Wanamaker was piling up DNPs before this week and got a chance to play some against both the Pelicans and Wizards. The guard had been playing in Europe since graduating from Pittsburgh in 2011 and signed with the Celtics during the summer.

“I thought Brad Wanamaker has done a good job in the last two games,’’ said Stevens. “He hadn’t gotten the chance to play as much before, but it’s not a big surprise. He’s a pro. He’s been doing this for a long time, just not in the NBA. His readiness is not a shock.’’

Hayward sat out the previous two games with an illness while Brown, who just returned from a back ailment, did not play in Washington.

Horford, who is dealing with a sore left knee, has missed four straight games and there is no timetable for his return. Yabusele suffered a sprained ankle last Saturday night in Chicago and will be out a few weeks.

Aron Baynes, who was sidelined two games with a sprained ankle, made his second straight start but remained on a minutes restriction.

“We’re going to keep him down again to 12 to 15, somewhere around that range,’’ said Stevens.

On the road: The Celtics boarded a plane right after the game for Detroit where they play the Pistons tonight (7:05 p.m., TV: NBC Sports Boston; radio: WBZ-98.5 FM).

It is the second and final trip this season to Detroit where the Celtics won, 109-89, on Oct. 27.

After that, the Celtics have a three-day break before a four-game homestand that runs through a Christmas Day matchup with the Philadelphia 76ers.

Nickname news: Williams has been tagged with the nickname “Time Lord,’’ in part because of his problems with being on time when he was first drafted by the Celtics.

President of basketball operations Danny Ainge said he preferred “Lob Williams,’’ something the rookie agreed with.

“It’s catching on, that’s all I can say,’’ said Williams of the Time Lord tag. “I could go with ‘Lob Williams’ over ‘Time Lord.’ ’’

On Friday, Timex, the watchmaker, chimed in on Twitter, “Hey #TimeLord @rob williams III – you’ve inspired us. Let’s talk!’’

Said Williams when asked about that potential partnership, “That’s a different story, man.’’

Jim Fenton may be reached at jfenton@enterprisenews.com. Follow him on Twitter at @JFenton_ent.