One game does not a rivalry make.
So as entertaining, intense and chippy as Sunday's Celtics-Knicks battle was to usher in the 2011-12 season on Christmas, that's not a rivalry again quite yet. Let's see the Knicks win the Atlantic Division or a playoff series against Boston before we give it anything more than an enmity tag, considering how long it's been since both teams were legitimate contenders in the same season.
Now, Celtics-Heat? Yeah, that's got the "R" word written all over it.
Remember, the Celtics were defending Eastern Conference champs last season, having knocked off both Dwyane Wade and the Heat and LeBron James and the Cavaliers en route to the NBA Finals during the 2009-10 campaign. That summer, the Heat put together its own Big Three and went on to knock Boston out of the playoffs in May en route to taking over the conference throne.
Boom, rivalry. Two teams competing for the same objective, each with a legitimate chance of obtaining it.
That rivalry will be resumed on the national stage Tuesday at AmericanAirlines Arena when the Heat -- fresh off a season-opening rout of the defending NBA champions, the Dallas Mavericks -- host the Celtics (8 p.m., TNT).
Boston players weren't quite in the mood to talk about their next challenge after Sunday's loss in New York. But make no mistake, the Celtics will be amped for this one.
The Celtics won't need any reminders about how last season ended. Without enough bodies to hold a worthwhile practice on the first night of training camp earlier this month, Celtics coach Doc Rivers dragged his team into the film room and went over highlights from Miami's five-game triumph in the Eastern Conference semifinals.
"We didn't get enough out of our team [last season]," Rivers said after the viewing. "We just watched some film of that [Heat series] -- just to refresh all of their memories. [The Heat] were the better team in that series, but we made mistakes. And I wanted to remind them of that. I thought that was important."
Important because, on paper, the Heat -- who were dealing with similar financial restrictions to the Celtics -- only got better this offseason, while some wonder if the Celtics did little more than tread water.
Miami made one of the offseason's biggest splashes by hooking Shane Battier at the mini mid-level and were still able to re-sign James Jones and Mario Chalmers. The only free-agent departures were aging veterans such as Jamaal Magloire and Mike Bibby.
What's more, Miami rookie Norris Cole, selected one spot after Boston's JaJuan Johnson in June's draft, looks like an immediate contributor, while Johnson -- who may very well have a bright future -- didn't get off the bench Sunday.
Make no mistake, Boston likes its reserve unit, and the Brandon Bass-for-Glen Davis trade in particular looks like it has potential for high returns. But the loss of Jeff Green for the season (heart ailment) really hurt the bench, and the Celtics will need the likes of Chris Wilcox (whom Boston spent its mini mid-level exception on), Keyon Dooling and even second-year guard Avery Bradley to make significant contributions. The arrival of newly signed Mickael Pietrus could help the Celtics, but it's unclear how soon he'll be ready to go.
That means on Tuesday we could see more of Sasha Pavlovic, who logged 15 underwhelming minutes in a starter's role against the Knicks. Rivers would prefer to keep Marquis Daniels with the reserve unit, so the team might have to continue leaning on Pavlovic, given his size and ability to defend the likes of James (even after Carmelo Anthony went off for 37 points on 10-of-17 shooting Sunday). The Celtics don't need offense from Pavlovic, but they need stout defense (avoiding fouls, especially those of the technical variety, would aid that cause).
The other X factor is whether Paul Pierce will be able to suit up. He skipped Sunday's game in New York and told reporters to Google "bone bruise" to understand the injury that has sidelined him since the start of training camp. Those that clicked on the "images" tab risked losing their Christmas dinners. It's hard to imagine a couple of days would be enough to get Pierce on the floor after missing Sunday's opener, but it would further hammer home the magnitude of this game if he were to suit up.
What does a December win mean to either team? In the standings, not much, save for an end-of-the-year logjam atop the East. Heck, the Celtics won three of four meetings last season, and how did that work out for them?
But there is something to be said for a psychological edge. After how the playoffs unfolded, the Heat would seemingly have the sort of confidence that suggests they've leapfrogged the Celtics and are no longer worried about the old guard. A win Tuesday, which would be the sixth win in the last seven meetings, would only confirm that notion.
For Boston, a win could help remind the Heat that they can't forget about the Celtics. After all, the only way a rivalry exists is if there's give and take on both sides.
Recent meetings suggest the Heat are pulling away. It's up to Boston to rekindle the rivalry before the flame goes out.
Chris Forsberg covers the Celtics for ESPNBoston.com.