In Chad Harbach's The Art of Fielding, it can't be said that Pella establishes a literal sports team the way the book centers around a college baseball team; however, she does help to pull a team together.
During the novel, Henry developed anxiety problems that threw off his game. His devoted friend Mike, whom Pella had also been dating, tried to do his best to calm him down and get him back in his game but to no avail. At one point, Henry becomes suspended from the school's team for missing games, and Henry goes into hiding in Pella's house. What's more, Pella sleeps with Henry, driving a wedge between her and Mike. Mike, due to his devoted friendship to Henry, especially feels jealous that Henry has turned to Pella instead of to himself. But soon, Pella tells Henry he either needs to start talking about his feelings, start taking antidepressants, or move out of her house--Henry leaves. Meanwhile, Pella's previously straight father begins an affair with another young man on the baseball team, Owen. When her father commits suicide, it's up to Pella to make sure that Owen's reputation is not tainted and to uphold the team members' spirits.
Pella does one insane act that miraculously pulls all characters together, including Henry, Mike, and Owen. She decides that since her father loved water, he will be happier being buried in the lake and solicits the help of Mike, Owen, and Henry to help her illegally move her father's body from the college cemetery to the lake. Their crazy adventure is successful and also gives Owen a private moment to say goodbye to her father and a chance for Mike and Henry to repair their friendship. Soon, all members of the baseball team are playing strongly, and Henry is even offered a contract to play for the Cardinals.
Hence, it is in this non-literal sense that Pella helps to establish and unite the team.