Carolina Panthers defensive end Mike Rucker announced his retirement Thursday. That's bad news for the Lions, who were hoping to land Florida defensive end Derrick Harvey with the 15th pick overall. The Panthers choose two spots earlier and now need to find a starter at that position in the draft.

The top ends — Virginia's Chris Long and Ohio State's Vernon Gholston — are probable top-six picks, with Harvey the next best on the board. When I first sat down to do my mock draft last week, I had Harvey slipping past the Panthers, who ranked 31st in the NFL in sacks last year. It was debatable at the time, but Rucker said two months ago he hoped to play one more season and Carolina has other pressing needs on the offensive line.

The Ravens at No. 8 and Bengals at nine also need help at end, though they'd find better value elsewhere. Regardless, it looks like the Lions will have to trade up if they want Harvey, who would help fill their pass-rushing void. With an extra third-round pick from the Shaun Rogers trade, they have the ammo to move. In fact, according to the draft value chart, that's all it would take to get to No. 12, where the Broncos could be willing trade partners.

Still, I don't see it happening. Not for Harvey at least. If you're looking for a potential trade scenario, the spot to watch is No. 7, where the Patriots want out and defensive tackle Sedrick Ellis — the real apple of Rod Marinelli's eye — might be available. Ellis is a ferocious penetrator who would thrive in the Tampa 2 defense. Moving up that high might be rich too rich for the Lions, both in terms of the money it'd take to pay Ellis and the booty they'd have to pay New England (probably a second- and third-rounders, one this year and one next), but that's the move to make if they want an impact lineman and one of the top talents in the draft.