"We played Dream basketball, forcing turnovers, contesting shots and running our offense up-tempo," McCoughtry said. "Sancho is a great player, but while she's gone, other people have a chance to step up."
McCoughtry scored 23 points and Jasmine Thomas added 13 to lead the Dream over the Seattle Storm 68-59 on Friday night.
McCoughtry, last season's leading scorer in the WNBA, also had team highs with nine rebounds, seven assists and five steals to help as the Dream improve to 5-1.
Tina Thompson and Temeka Johnson scored 11 points apiece for the Storm, who dropped to 1-3.
The Dream played the first of six games without Lyttle, their leading rebounder and second-leading scorer this season. With Lyttle playing overseas for Spain's national team, Le'Coe Willingham started in her place and went scoreless but did haul in eight rebounds.
Lyttle is expected to return before a July 9 game against Minnesota. Her absence gave Atlanta coach Fred Williams a chance to give additional minutes to Tiffany Hayes, Aneika Henry and Willingham, a trio that lacked offensively, but did a good job stepping in Seattle's passing lanes and disrupting their offense.
"Getting more subs in, more fresh legs in (is important)," Williams said. "Offensively we got some things off the boards, some putbacks, and we had a few more set plays when things kind of slowed down."
Seattle, the league's lowest-scoring team, managed just four points in the third quarter coming on two baskets by Johnson and trailed by 16 before an 11-1 run pulled them to 58-52 on Camille Little's layup midway through the fourth.
But that was as close as the Storm would get. Erika De Souza stole the ball from Tanisha Wright a few minutes later and passed it upcourt to McCoughtry for a fast-break layup and a 10-point lead.
"We just have to be aggressive," Johnson said. "Take what we want, not what people give us. And have the taking mentality in the third quarter."
Williams could tell in the first 4 minutes of the third that his team was ready to take control of the tempo.
"I told them in the huddle to come out on fire," Williams said, "to get in the passing lanes and gamble for some buckets."
Alex Bentley added 11 points for Atlanta, which leads the league in team defense, allowing 68.7 points per game.
The Storm used a 17-3 run in the first, ending on Shekinna Stricklen's layup, to take a 19-13 lead in the last 2 minutes of the quarter.
Seattle either led or tied for most of the second before McCoughtry stole the ball from Wright with 2.9 seconds before halftime and hit a layup at the buzzer to put Atlanta up 38-35.
The Storm, coming off a nine-point home loss last week to Tulsa in which they went 0 for 17 from 3-point range, hit seven of 19 attempts but Thompson and Stricklen were a combined 1 for 8 from beyond the arc.
"We're going to have to just keep fighting," Thompson said. "We're not going to give in. Just going to keep fighting. Keep working, getting better, executing. I think that if we continue to focus on that then we'll be OK."
McCoughtry promised to keep her teammates from falling into a collective funk without Lyttle.
"This is a good team, but we can get a lot better," McCoughtry said. "There's a lot of stuff to clean up, but we're off to a pretty good start."