Depth is one of the most important aspects of team sports. You need it when a player is injured, tired or in a slump. It’s what separates the great teams from the good ones.

Two weeks into World TeamTennis play, the Philadelphia Freedoms have learned that they have depth.

Every player was fresh after the first three matches, so minimal lineup changes were needed. Since a day off last Thursday, the Freedoms played five matches in six days. That was the ultimate test and because of their depth, they passed and went unbeaten.

“When you switch one out, you’re not forgoing the opportunity to win that set,” said Donald Young, who is in his fourth season with the Freedoms. “That’s been great in having so many options where almost everyone can play every role on the team if they have to.”

The Freedoms (7-1) moved into sole possession of first place Tuesday after defeating the Chicago Smash (6-2), 23-19. That win was followed by a dominant 25-16 victory against the Vegas Rollers (4-5) on Wednesday.

The Freedoms have used different lineups in men’s, women’s, and mixed doubles. Young and Taylor Fritz have both played men’s doubles with Fabrice Martin, and each pairing offers something different.

“With Taylor, you have a really big serve, and if you get me out there, maybe I can do some things at the net and just give them a different look,” Young said.

Taylor Townsend and Caroline Dolehide played the first four matches together, but then Sofia Kenin joined the action. Women’s doubles have used three pairings (Kenin-Dolehide, Townsend-Kenin, and Townsend-Dolehide).

Coach Craig Kardon has used his reliable duo Martin-Townsend for mix doubles in seven matches. Young played with Townsend in the other.

“There’s a lot of choices, and everyone is getting along great,” Kardon said.

Championship-caliber roster?

The roster of six has three new players and three veterans. Young is one of those veterans, and he’s been on the the past two teams, which were No. 1-playoff seeds. The team added the 2020 Australian Open singles champ (Kenin), the third-ranked American women’s doubles player (Dolehide), and the second-highest ranked American men’s singles player in Taylor Fritz.

“When you look at those squads, it’s definitely probably the toughest on paper and as far as the results so far,” Young said. “I think this squad can really do some damage and maybe take a title.”

Kardon has emphasized the importance of having fun to this year’s team. He believes it can be the main difference between this squad and the last two No. 1 seeds.

The team has done that so far. They’ve gotten together for team dinners, and team outings on the rare off days.

“Most importantly, we have to continue to have fun and enjoy the competition,” Kardon said. “They are having fun. Everyone on this team loves to compete, so that’s a win.”

The Freedoms return to action Friday at 3 p.m. on the Tennis Channel against the Orange County Breakers (3-5).