The pursuit of a number one centre will be Brian Burke’s top priority this summer. Of course you already know this because Brian Burke isn’t shy with his opinions and the Toronto media loves to run wild with any piece of informational nugget that Burke throws them.There are a few options for the Leafs, each with their own positives and negatives. First, the Leafs can open their deep wallets and shell out major cash for a premier free agent on July 1st. The only player who is a legitimate star centre is Brad Richards, who has all but left Dallas already.The second option if the Leafs are unable to sign Richards is to acquire a centre through trade. The Leafs have finally collected a stable of legitimate prospects, in addition to two first round picks in this year’s entry draft, which means that the Leafs could actually be a realistic destination for a top-6 player. And because we’re talking about the Leafs, you know thinking about keeping prospects is fruitless.Another option would be to present an offer sheet to a restricted free agent. For example, Steven Stamkos is a RFA and has yet to sign with the Lightning (although reports indicate they are close). The Leafs could offer him a massive deal on July 1st and hope the Lightning refuse to match it. However, the Lightning have ample cap space and losing a 21-year-old who has scored close to 100 goals over the past two seasons is unthinkable. Even if the Lightning do not match, which is highly unlikely, the Leafs would compensate Tampa with four first round picks.Finally, and least appealing, would be going with an in-house option. Last year the Leafs tried slotting Tyler Bozak in the number one spot, which didn’t work, and soon the Kulemin-Grabovski-MacArthur line became the de facto number one line, although no on really called them that. Grabovski wouldn’t be a horrible number one centre; he scored 29 goals and 59 points last season. But he isn’t an ideal option. He certainly isn’t a star capable of carrying his team on a nightly basis and that’s what the Leafs are looking for.The Leafs have both Nazem Kadri and Joe Colborne on the cusp of becoming NHL regulars, but the former might be better suited for the wing in the NHL and the latter has all of one game of NHL experience in his career. Expecting either of these players to assume even a second line duty is probably excessive. One, or possibly both, could use more time in the AHL before being expected to contribute in a top-6 role.The option that will cost the Leafs the least – in terms of actual non-monetary assets – would be signing Richards. But is this the best option for the Leafs long-term?Brad Richards has 716 points in 772 career games. The last two seasons he scored 77 and 91 points respectively. He has scored 62 points in 63 career playoff games and has already won a Stanley Cup and a Conn Smythe Trophy.Richards can log big minutes; he averaged over 21 minutes a game this past season. He also can play the point on the power-play, which will negate the Leafs’ need to sign a puck-moving defenceman. Because of his versatility he averaged more time on the power-play than any other forward besides Sidney Crosby.Last season, Richards’ cap hit was $7.8 million. Because of his skills and the extreme dearth of front-line players this off-season, Richards will command at least $7 million per season again. The three major teams rumoured to have serious interest in Richards are Toronto, New York, and Los Angeles – three big market teams with plenty of cap space. If there is a bidding war between these three teams, it isn’t inconceivable to think that Richards’ cap hit could exceed $8 million per season. The deal will certainly be at least five years as well.Richards is 31-years-old and a five-year deal will mean he will be making at least $7 million as a 37-year-old at the end of the contract. Martin St. Louis (36) and Teemu Selanne (40) both scored well over a point-per-game this season, meaning that it isn’t impossible for someone in their late-30s to continue producing as a top-10 scorer in the league, but it certainly isn’t the norm.Plus, Richards is a pure offensive player. He is a career -72 and only has three seasons where he doesn’t have a negative +/-. He doesn’t kill penalties and he doesn’t take many defensive zone face-offs, which is understandable considering he wins only 50.6% of his draws.It’s clear you’re only paying for offence with Richards, but as long as you have other players capable of playing in defensive situations, this isn’t a huge problem provided Richards scores.More importantly, Richards is the perfect complementary player for Phil Kessel. Richards is an excellent set-up man and averages over 40 assists a year; he has twice flirted with 70 assists in a season and with Kessel on the wing there is the potential for magic for both players (I can already see dreams of 50 goals flashing through my head). With the discouraging regularity that Kessel falls into his seemingly endless slumps, it is clear the Leafs need a player with the consistency of Richards.The major concern isn't this season, but long-term. Richards would certainly help make the Leafs a serious playoff contender this upcoming season, but a $7+ million cap hit could become onerous later when younger players are in need of serious raises. Yes, the cap continues to climb, but Richards could become a contractual anchor if his play declines.There are some injury concerns as well. Richards suffered a concussion at the end of last season and missed a total of 10 games. Investing in a 31-year-old coming off a concussion is a frightening proposition. Richards’ play did not slip after returning from the injury, but the Leafs must ensure Richards is fully healed before committing major dollars to the talented pivot.Signing Brad Richards clearly is a risky venture. If the Leafs choose another route, a trade is the most likely alternative. Jeff Carter, Stephen Weiss, and Paul Stastny have all been linked to trades at some point over the past season, so let’s hypothetically examine their availability and whether the Leafs should try to pry them out of their current locale.Jeff Carter is a great two-way centre who has once scored 40+ goals and 80+ points. He’s only 26 and has a modest cap hit of $5 million (of course it does last for 11 years). He wins almost 55% of his draws and takes more defensive zone face-offs than any other Flyer.So why would the Flyers ever think of dealing Carter? Well, according to Nick Kypreos of SportsNet, the Flyers are going to sign Ilya Bryzgalov for roughly $7 million per season. The Flyers are already pushed tight to the cap and will need to shed salary if Bryzgalov does indeed sign. Jeff Carter’s name is constantly brought up as a candidate for relocation, but the Flyers could move other players like Matt Carle and Kris Versteeg to come up with the needed money. Plus, the Columbus Blue Jackets are reportedly willing to give up Jakub Voracek and this year’s 8th overall pick for Carter, which is a sum I don’t think the Leafs could match.Stephen Weiss scored 49 points this season after two straight 60 point seasons. Weiss has two more seasons at a reasonable $3.1 million cap hit. Considering he hasn’t registered any major statistical numbers in his career, the Leafs might be able to obtain him for a lower price than some of the other alternatives. However, Weiss really isn’t an upgrade for the Leafs and would basically give them another version of Mikhail Grabovski. If the Leafs get Weiss on the cheap as a stop-gap option until some of their prospects are ready to step in this could be a good plan, but if the Panthers demand some of the Leafs’ top prospects it’s probably wise to move on.Finally, Paul Stastny keeps popping up in trade rumours, despite being Colorado’s number one centre. I’m unsure why this is the case, but let’s just imagine he is available. He is only 25 and has scored over 70 points in three of his five NHL seasons. He has three more seasons on a deal with a $6.6 million cap hit, which is a decent rate for a first line centre, provided he can rebound from a sub-60 point 2010-2011 season. The Leafs would certainly have to trade some of their best prospects, but Stastny is young enough and with a productive enough track record to make a deal palatable.If the Leafs are unable to land Richards and fail to acquire a centre through trade, Leafs Nation will need to exercise patience and hope that either Nazem Kadri or Joe Colborne can eventually become a number one centre. If they do, avoiding a potentially cap killing contract will be the best move Burke made this off-season.