Virginia Tech guard Erick Green (11) fights through a screen to get to Boston College’s Lonnie Jackson. BC handed the Hokies their sixth loss in seven games, 86-75. (Daniel Lin/ASSOCIATED PRESS)

Virginia Tech Coach James Johnson and his staff have used every defensive drill they know during practice in recent weeks, hopeful a team that has become increasingly foreign to the concept could somehow change its ways.

The Hokies’ defense was once again porous Wednesday, as they dropped their fourth straight game by double digits, losing 86-75 to Boston College in front of 6,054 at Cassell Coliseum.

The Hokies were done in by a defense that allowed the Eagles to shoot 56.3 percent from the field after halftime and an offense that was without a key cog and committed 17 turnovers, Virginia Tech’s second-highest total.

But considering the Hokies are just a month removed from their best start in 30 years, the current skid has begun to wear on a roster that was already fighting an uphill battle because of defections and injuries. Even worse: Boston College was picked to finish last in the ACC this preseason and Virginia Tech was coming off three losses by 23 or more points for the first time in program history.

“We do it in practice, but I don’t know, we’re just not translating it into the game,” senior guard Erick Green said. “It feels long. It feels like we lost six, seven straight.”

Green (Paul VI Catholic) was again one of the lone bright spots for Virginia Tech (9-6, 0-2 ACC). He entered Wednesday’s game as the nation’s leading scorer and accounted for 10 of the Hokies’ 29 field goals, finishing with 24 points and nine assists. Forward Jarell Eddie added 21 points, but he also committed a team-high five turnovers.

Boston College (9-6. 1-1) made sure those miscues didn’t go to waste. The Eagles scored 29 points off Virginia Tech’s giveaways and finished with 42 points in the paint, ensuring the Hokies will remain the ACC’s worst team in terms of scoring defense. Forward Ryan Anderson led Boston College with 26 points and nine rebounds and guards Lonnie Jackson and Olivier Hanlan added 22 and 17 points, respectively.

“Twenty-nine points off of turnovers, we can’t guard that,” said Johnson, whose team has gone 2-6 since starting the year 7-0.

For the second straight game, Virginia Tech only used six scholarship players. Five days after Johnson benched power forward C.J. Barksdale for a lack of effort at Maryland, he had to make do without sophomore Robert Brown. The Hokies’ third-leading scorer had an illness and was sent home following a Wednesday shootaround.

Johnson said after the game he was hopeful Brown would be healthy enough to play at Georgia Tech on Saturday. Barksdale was inserted back into the starting lineup and finished with six points and four rebounds before fouling out.

Boston College never trailed in the second half and led by as much as 12 points after entering halftime on a 10-0 run. The Hokies, who shot 64.3 percent in the second half, closed to within three when Barksdale connected on a layup with seven minutes remaining. But Virginia Tech never could seem to get a defensive stop when it needed one.

The final score could have been worse had Boston College not missed 15 of its 35 free throw attempts. That, though, was of little consolation to Virginia Tech, which suddenly finds itself in a free fall.

“Right now,” said Eddie, his eyes locked on the ground below, “we’re in a tough place.”