CINCINNATI -- The search for defensive linemen who can improve the Cincinnati Bengals' pass rush has begun.

Indications are the organization would like to use both free agency and the NFL draft to address the pressing issue. The bulk of the emphasis, though, is currently being placed on free agency. If they can get them, the Bengals would like to add a veteran player or two who have already proven they can get to an opposing quarterback.

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For a defense that had Pro Football Focus' worst pass-rush grade this past season, and one that finished with 20 sacks -- one of the lowest single-season totals in franchise history -- the reasons it's important to bolster the defensive line are infinitesimal.

With the start of free agency now less than a week away, it's a good time to come up with ways to best identify free-agent pass-rushers.

Earlier this week, ESPN insider and former NFL general manager Bill Polian published his 2015 free-agent big board . In it, he also outlined 14 dos and don'ts for league executives as they search for veteran talent this offseason.

One of them made perfect sense, especially when applied to pass-rushers: "Don't give A- or B-money [or years] to a player who doesn't play well on third down."

For a defensive lineman, third downs are when he earns his salary.

Polian considers "A" money earners to be those who ought to have $6 million or more of annual average value with three-plus years of guaranteed money placed on their new deals. He considers "B" money earners to be those who should have an annual average value between $2-6 million with two years or less of guaranteed money.

Traditionally, on the top end of their free-agent spending, the Bengals go after "B" money free agents.

George Johnson and Greg Hardy are two ends who Polian thinks meet his "B" money criteria.

Perhaps the least-recognizable name from the Detroit Lions' defensive line, Johnson is a former undrafted free agent who had a breakout season in Detroit's rotation. He was the equivalent of what Wallace Gilberry was for the Bengals in 2013. Before getting thrust into more playing time as the Bengals sought to replace Michael Johnson this past season, Gilberry was Cincinnati's No. 3 defensive end. A third-down specialist, Gilberry did his best damage two seasons ago in clutch situations.

As for Hardy, the Panthers' defensive end who had domestic violence charges dismissed last month, the numbers this past season were essentially nonexistent. He only played in one game due to the charges. It's unclear if he'll miss any more time in 2015 because of the off-field incident that led to them. Before the trouble, Hardy had 15 sacks in 2013 and 11 in 2012.

If Polian's rule about third-down play was to be applied to Johnson or Hardy, this accompanying charts show both would deserve getting paid. Who else might?

To find an answer, we looked at third-down numbers of some of the current notable free-agent pass-rushers. In an effort to account for Hardy's missed time, and to also avoid giving too much credence to players who may have had strong performances in contract years, we looked at numbers not only from 2014, but from 2013, as well.

While Ndamukong Suh would be the ideal addition, because of his anticipated mammoth contract, don't expect him in Bengals stripes. But cheaper options such as Jerry Hughes, who had six third-down sacks the last two seasons, also exist. So does Johnson and Hardy, among others.

Notable Free-Agent Defensive Linemen on Third Downs, 2013-14 Player Snaps Tackles Sacks Games 2014 Cap Value Jerry Hughes, BUF 387 14 6 32 $3,995,000 Greg Hardy, CAR* 214 12 6.5 17 $13,120,900 (franchise tag) Jason Pierre-Paul, NYG 320 16 6 27 $4,611,000 (franchise tagged this year) Jared Odrick, MIA 384 15 5 32 $2,779,873 George Johnson, DET** 141 11 4 16 $570,000 Nick Fairley, DET 205 8 3.5 23 $3,146,500 George Selvie, DAL 231 8 3 32 $730,000 Ndamukong Suh, DET 396 18 8 32 $22,412,000 Corey Peters, ATL 240 8 3 30 $1,468,750 Source: ESPN Stats & Information *Missed all but one game in 2014 while on exempt list. **Reserve in 2013 who was cut that October by Minnesota. Didn't play a game that season.