After two successful 10-day contract performances, the Boston Celtics will sign forward Chris Johnson for the rest of the season, league sources told Yahoo Sports.

Boston's front office and coaching staff had been fond off Johnson, but signing him pushed the Celtics precariously close to the luxury tax line. Nevertheless, the Celtics were ultimately too impressed with his performance to let him leave.

Johnson has played well for the Celtics since his call-up from Rio Grande Valley of the NBA Development League in January. Johnson, 23, has averaged 7.6 points in 21 minutes, including 40 percent shooting from three-point range.

Johnson played college basketball at the University of Dayton.