Boston, the No. 1 overall pick in this year's draft, led all players in points, rebounds and assists, making her the first rookie in WNBA history to do all three in a game, according to Elias Sports Bureau.
Indiana snapped a six-game losing streak, scoring its first double-digit victory since 2021. The Fever trailed 45-41 early in the third quarter before scoring 18 of the next 20 points to take control at 59-47.
Kelsey Mitchell added 19 points and NaLyssa Smith, who scored a career-high 27 points on Sunday, had eight points for Indiana (3-6). Boston was 11-of-14 from the field to became the youngest player in WNBA history with a game of 20 points, 10 rebounds and five assists while shooting 75%, according to ESPN Stats & Information.
Mitchell moved into second place on Indiana's all-time scoring list, passing Katie Douglas (2,564). Tamika Catchings holds the record with 7,380 points.
Elena Delle Donne was the lone double-digit scorer for Washington (5-4) with 17 points. The Mystics were held to 22-of-66 shooting (33%).
The Associated Press contributed to this report.