A strong defense is vital to what the Blackhawks want to do, and that's why general manager Stan Bowman sees no problem with investing millions in his blue line, the most instrumental part of the Hawks' puck-possession game. ''The defense is the key that makes everything go for us,'' Bowman said Saturday. ''We've got a lot of really skilled forwards, and the style of hockey we like to play is dependent on having mobile, puck-moving defensemen.'' So it shouldn't be much of a surprise that defenseman Brent Seabrook is in line for a big extension. Canada's TSN first reported early Saturday that the Hawks and Seabrook's camp were on the verge of finalizing a five-year extension for nearly $30 million. Additional reports indicate Seabrook's contract — his third with the Hawks — will pay him between $5.6 million and $5.8??million annually. If those numbers are accurate, the Hawks will have a defensive corps that costs around $24 million against the cap, factoring in Duncan Keith ($5,538,462 cap hit), Brian Campbell ($7,142,875), Niklas Hjalmarsson ($3,500,000) and Nick Leddy ($1,116,666). Seabrook currently makes $3.5 million. ''We believe [Seabrook has] been instrumental in getting us to the point we're at, and he's going to be instrumental in keeping us at this level,'' Bowman said. ''He's at a good young age [25]. He's really just entering the prime of his career." Seabrook has 33 points and a plus-2 rating in 61 games. He has moved up to the first power-play unit while remaining a cog on the penalty kill. He's also consistently physical.