The big day has finally arrived as the NHL's annual trade deadline day is now upon us, with several high-profile trades having already been made and many teams looking to make deals before the 3PM ET deadline.

The Toronto Maple Leafs have been one of the most active teams prior to the deadline, making a grand total of four trades in a span of nine days from Feb. 9-18. The biggest of which was the much anticipated trade that sent veteran defenceman Tomas Kaberle to the Boston Bruins for Joe Colborne, a 1st round draft pick in 2011, and a conditional 2nd round pick in 2012.

Despite Leafs GM Brian Burke having been so active pre-deadline, it does not appear as though trade deadline day will be a quiet one in a Leafs Nation. Here is a look at what Burke might do before the 3PM deadline.

Needs

Defenceman - When the Leafs traded Kaberle to the Bruins, it created a large hole on the blue line that has yet to be filled. Kaberle was a veteran presence in the locker room and a solid offensive defenceman.

Burke thought he was on the verge of acquiring a defenceman as he stated at a Family Day event on Feb. 21 that he hoped to be able to add a rearguard by the next day. That did not happen however and the Leafs are still on the hunt for a puck-moving blue liner, which Burke has identified as his biggest need.

The big name being floated about is John-Michael Liles of the Colorado Avalanche. Liles has six goals and 35 assists for a total of 41 points in 63 games with the Avs this season. If he were added to the Leafs lineup, he would be just the second player on the roster over the age of 30, alongside goaltender J.S. Giguere.

Liles comes with a hefty price tag in the form of a 4.2 million cap hit which runs through the end of the next season. The asking price for Liles is also rumoured to be high with some reports stating the Avalanche are looking to acquire a 1st round draft pick in exchange for the 30-year old American defenceman. It is possible that as the day progresses and should the Avs be anxious to shed salary, that price could decrease.

Other possible defencemen the Leafs have been rumoured to have been interested in at one point or another include: Zach Bogosian, Cam Barker, and Barret Jackman. The Ottawa Senators are also reportedly interested in trading blueliners Chris Campoli and Filip Kuba.

Centre - A knock on the Leafs for the past few seasons has been that they are soft up the middle and are in need of a legit top six centreman. While Mikhail Grabovski has filled that role as well as anybody could have hoped for this season, could this be the day that Burke addresses his needs at centre.

Dallas Stars forward Brad Richards would be a great addition to the Leafs and has long been rumoured to be of interest to Brian Burke. Stars GM Joe Nieuwendyk has stated that he has listened to offers for Richards, but the asking price is believed to be very high.

In a report in the New York Post, Nieuwendyk was reported to have asked for three roster players from the New York Rangers which included Marc Staal, Brandon Dubinsky and Derek Stepan in exchange for Richards. Do the Leafs have those types of assets to trade away? And would Burke willing to part with that type of a package for a possible rental player.

Other forwards the Leafs have at points been rumoured to have been interested in include: Stephen Weiss, Dustin Penner, and Paul Stastny.

Current Leafs Who Could Be Traded

Clarke MacArthur
Despite several contract negotiation sessions, the Leafs and forward Clarke MacArthur have been unable to agree on a contract extension prior to the trade deadline.

Several teams are interested in MacArthur and it is easy to understand why as the 25-year old forward is having a career-year with 19 goals and 29 assists for a team-leading 48 points.

A report on Sunday indicated that the Nashville Predators were willing to offer J.P. Dumont and defenceman Ryan Ellis in exchange for MacArthur. It is also believed that MacArthur will fetch the Leafs a higher return than what they acquired for Kris Versteeg. Burke sent Versteeg to the Philadelphia Flyers on Feb. 14 for a 1st and 3rd round draft pick in 2011.

Mikhail Grabovski
This seems very far fetched, but there are teams interested in acquiring Mikhail Grabovski to make a run for the playoffs.

Grabovski has been a revelation for the Leafs this season, with 24 goals and 22 assists for a total of 46 points. The question becomes would Burke be willing to deal one of the offensive bright spots on his team who is signed through the 2011-12 season.

Draft Picks
Brian Burke has stated that the third round pick he acquired from the Philadelphia Flyers on Valentine's Day is in play and that he had offered it to a team for a forward. In addition to the third round pick, the Leafs also have two first round picks in this year's draft which they could parlay into addressing their needs.

Cap Space
One of the benefits of dealing Francois Beauchemin, Kris Versteeg, and Tomas Kaberle is that the Leafs have created a great deal of cap space.

It is projected that the Leafs have around $5.2M in cap space which could go along way into working on helping a team looking to dump salary in a trade that would also address one of Toronto's needs on the blue line or at centre.

Stay tuned to HockeyBuzz.com all day for the latest on trade deadline day rumours and deals. For up-to-the-minute Leafs news and updates, be sure to follow Ken Beckett on Twitter @KenBeckett.>