BOSTON -- Clemson came onto the court with a national ranking for the first time in nearly eight years and completely controlled Boston College in the opening half.
In the second, they made just enough plays to hold off the Eagles.
"Our team just locked in defensively," Grantham said. "Tonight, in the first half, it was special. When we get locked in like that, I don't see too many teams beating us."
Reed finished with 17 points for the Tigers (13-1, 2-0 Atlantic Coast Conference). Clemson's last time in the AP poll came on Jan. 23, 2010.
But the Tigers had to withstand an incredible shooting performance by BC's Jerome Robinson in the second half. He went 10 for 14 from the field, hitting 6 of 9 from beyond the 3-point line.
"That's why when you have a lead you need to keep building it because you never know when a guy can take over a game," Clemson coach Brad Brownell said. "Robinson had some unbelievable confidence. We couldn't get him under control."
Robinson led Boston College (10-5, 1-2) with 28 points, scoring 26 in the second half. Ky Bowman had 19 with nine rebounds and six assists.
Reed nailed his two from the line with 48 seconds left to move Clemson ahead 70-68. Robinson's 3 from the right wing rimmed out on the next possession.
"I got some space and I was like: `I'm going to let it go," Robinson said. "I had already hit two or three from that spot and we needed that one and unfortunately it didn't go."
Bowman's driving basket cut it to 68-66 with 2:19 to play, the third time BC sliced a big deficit to two points, before he tied it with two free throws with 1:02 left.
Trailing by 15 at halftime, the Eagles relied on a strong start by Robinson, a second team preseason all-ACC selection, after the break. The 6-foot-5 junior guard scored 19 points, including going 5-for-5 on 3-point attempts in the opening 10 minutes to slice the deficit to 53-50.
"We became who we are," BC coach Jim Christian said. "In order to win in this league, you have to play more than 20 minutes."
The Tigers had used a 16-0 run midway into the first half en route to their 38-23 halftime.
Grantham, who had a team-leading 11 points and nine rebounds in the half, scored eight straight points in the opening 20 minutes.
Clemson: The Tigers' emergence in the poll may last a while. Entering the game, they had all five starters averaging double figures in scoring. ... Won its sixth straight against BC.
Boston College: Facing their third consecutive ranked team looked like it took a lot out of the Eagles. They appeared flat at the start -- something an average team can't afford. After that, they showed they can compete -- like in their win over then-No. 1 Duke in the league opener and a one-point loss at No. 8 Virginia on Saturday.
"We can't take our eye off the prize," Christian said. "We can't have a 3-minute lull or a 4-minute lull like we had in the first half. You can't dig those type holes."
Grantham, a 6-8 senior forward, became the sixth player in school history with 1,000 points, 500 rebounds and 200 assists.
BC didn't have an offensive rebound in the opening half, was outrebounded 20-10 overall and went over 5 minutes without a basket.
Eagles starting forward Nik Popovic picked up three fouls in 5 minutes in the half.
It was Robinson's seventh game with 20 or more points.
Clemson: Hosts Louisville on Saturday.
Boston College: Hosts Wake Forest on Saturday.
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