Marcus Landry could face huge test

Welcome to Boston, Marcus Landry. Now go guard LeBron James.

Utilizing Landry -- a rookie forward obtained with Nate Robinson as part of a five-player swap with the New York Knicks at last week's trade deadline -- to defend one of the NBA's top talents isn't exactly an ideal situation for the Boston Celtics. But coach Doc Rivers admitted Wednesday it's one potential scenario his ailing team is bracing for when Boston hosts the Eastern Conference-leading Cleveland Cavaliers on Thursday night at the TD Garden.

Both Paul Pierce (sprained thumb, flu) and Marquis Daniels (illness) sat out Wednesday's practice. Rivers said Pierce "most likely" will not play Thursday. Daniels will be re-evaluated closer to game time but "looked terrible," according to Rivers, and was sent home.

That means Boston, winner of four of its last five, could be without the two players at the top of its small-forward depth chart in a matchup against a player who is arguably the top small forward in the history of the game.

"If Marquis doesn't play, and if Paul can't go, I don't know who we'd put on [James]," admitted Rivers. "Using my basketball knowledge, it's not very easy to guard him on any night, so it'll be tough [Thursday] night too.

Of using Landry, Rivers said, "We may have no choice. It is what it is. [Point guard Rajon] Rondo may have to guard him. Seriously."

Rondo is one of the top defenders in the NBA, easily leading the league in steals. But if the 6-foot-1, 175-pound guard matches up against the 6-foot-8, 250-pound James, it's clearly a mismatch that favors the Cavaliers.

The mere suggestion of a Rondo-James pairing underscores the problem Boston could encounter if Pierce and Daniels can't suit up. Pierce sprained his right thumb in a win last week against the Lakers, struggled through a couple of games, then sat out Tuesday's triumph over the Knicks (while also battling the flu).

Daniels, who missed 28 games earlier this season after undergoing surgery to repair torn ligaments in his left thumb, drew the start against New York and scored 14 points to help Boston emerge with a 110-106 triumph, but started feeling ill after the win.

The Celtics like Daniels' ability to lock down an opposing scorer while coming off the bench.

"We [tell Daniels], 'Why don't you just try to stop him,'" Rivers said of Daniels' role of defending the opposition's best scorer. "And we don't have to help as much, which makes our defense better."

Short on small forwards -- Ray Allen and Tony Allen are better considered pure shooting guards -- Rivers went so far as to suggest that Landry, who didn't get off the bench in his first game in a Boston uniform Tuesday, might get a crack at James.

For his part, Landry said he's ready for that situation ("It'd definitely be a good challenge for me," he said), but the Celtics would probably rather avoid it.

It's just one of the many storylines to watch as Boston and Cleveland prepare to clash for the first time since opening night, when the Celtics rallied from a first-quarter deficit for a 95-89 triumph at Quicken Loans Arena.

Plenty has changed since that night, when James and Shaquille O'Neal played their first regular-season game together. Most notably, the Cavaliers added power forward Antawn Jamison before the trade deadline, beefing up a frontcourt that already presented matchup issues for Boston.

Rivers admitted there is very little his team can extract from that first meeting in late October.

"They're not the same team and, hell, we're not even the same team," said Rivers. "We won [the first meeting], we can take that away, but both teams probably forgot about that by now. Watching them on tape the last two games, the Jamison [addition] has changed them a little bit. It definitely makes them more difficult to guard and we have to be ready for that."

Not surprisingly, the Celtics downplayed the importance of Thursday's game. Boston's struggles against the top teams in the East (1-7 vs. the Magic and Hawks) have been well-documented and, considering this is the first of three more meetings between Boston and Cleveland over the final 27 games of the season, the Celtics attempted to ignore the usual "measuring stick" chatter.

"It's a game that we want to win; we're trying to put together a string of victories," said veteran Ray Allen, who appears to be emerging from his first-half struggles with the NBA trade deadline safely behind him.

"We'd like to protect home court and, as we finish up the last 30-something games, attention to detail is important."

One not-so-minor detail focuses on how Boston plans to slow James, particularly if Pierce and Daniels can't go.

"Everybody knows how LeBron is," said Robinson. "He gets everyone involved. He's one of the best in the league. We've got to be ready to compete. It's the highest level of competition, he's one of the best players in the world. We've got to attack him."

And if that means the Celtics have to lean on Landry, a 6-foot-7, 230-pound defense-first forward out of the University of Wisconsin, so be it.

"He's a tough kid who likes to defend," Rivers said. "We've got to teach him NBA defense, but he has the chance to be an NBA defender, no doubt. If we need him, Marcus might just get a little piece of him."

Him being King James.

Chris Forsberg is the Celtics reporter for ESPNBoston.com. Follow him on Twitter.