Entering its 51st year as the pinnacle of hockey season in the Hub, the Beanpot Tournament commences tonight at 5 p.m., pitting Harvard against the team that has made the tournament its own over the first fifty years of the Beanpot’s existence.

The Boston University Terriers (15-10-2) have won the Beanpot 24 times in a half-century of play and are currently ranked directly behind the Crimson in the USCHO.com national rankings.

Harvard (13-6-1), ranked No. 13 in the latest poll, won its first game back from the exam period break, skating quickly and checking aggressively in a 3-1 win over Brown Friday night.

The absence of a dull edge, a yearly Crimson post-exam hallmark, may have resulted from a change instituted this year by Harvard coach Mark Mazzoleni. Instead of a traditional January exhibition game, Mazzoleni and his coaching staff staged a three-day training camp to get the players back on their games.

The camp was intended to avoid another disastrous post-exam skid. Last season, the Crimson suffered through a 2-8-1 stretch from the end of exams to the start of ECAC playoffs, a slide that included Beanpot losses to both Northeastern and Boston College.

Recent Hub hockey history is on BU’s side, of course. The Terriers have won seven of the last eight tournaments, including a 2-1 overtime win in the 1998 tournament final.

The Crimson’s last two regular season games against BU have also gone the Terriers’ way. BU won 8-4 last season at Bright and shut Harvard out, 3-0, earlier this season at Walter Brown Arena.

The Terriers last played Thursday night against Hockey East opponent Merrimack, emerging with a 5-0 victory. Still, Harvard is catching a reeling BU, which has lost four of its last six games.

And unlike in years past, the Hockey East schools (BU, BC and Northeastern) will not have an easier schedule going into the Beanpot.

In previous years, Hockey East has arranged its league schedules such that its teams play only one game, usually at home, the weekend before their Monday Beanpot contest. On the other hand, the ECAC had always forced the Crimson to play two games before the Beanpot, often on the road.

This year, Mazzoleni succeeded in lobbying the league office for a change, and Harvard will only play on the Friday nights before Beanpot games, a change that levels the ice for the Crimson.

Despite their struggles of late, the Terriers are still one of the best teams in the country, representing both a challenge and an opportunity for Harvard.

“We need to seize the moment,” Mazzoleni said. “We definitely have the ability to play with these teams, but playing with them is one thing, beating them is another.”

“It’ll be a great opportunity to showcase what we can accomplish this year,” sophomore goaltender Dov Grumet-Morris added.

Solid goaltending will not be enough to overcome BU, though. In the 3-0 loss at Walter Brown Arena in November, Grumet-Morris turned aside 29 shots, but was overshadowed by BU goaltender Sean Fields, who stopped 36 in the shutout.

In addition to Fields, the Terriers boast a solid compliment of skilled forwards, including junior Frantisek Skladany and senior John Sabo. BU’s blue line is anchored by sophomore Ryan Whitney, who rivals Harvard sophomore Noah Welch for the title of best defenseman in town.

For the Crimson to beat BU, it will have to capitalize on Terrier miscues. Successfully jumping on BU mistakes was a key factor in Cornell’s pair of wins over the Terriers earlier this season.

“BU is a very high-energy team,” Mazzoleni said. “They’re an emotional team. That’s one of the reasons why BU is the most penalized team in Hockey East. They play highly emotional, and that can go against them. We’ve got to be emotionally even and disciplined and not take unnecessary penalties.”

If Harvard succeeds in doing that, it may end a four-year drought and finally reach the Beanpot Championship. If that happens, it may end the second Monday in February hosting the pride of Boston high overhead, a feat not managed in Cambridge since 1993.

—Staff writer Timothy M. McDonald can be reached at tmcdonal@fas.harvard.edu.