When the NFL announced rosters for the Pro Bowl this week, it was a reminder that the Seattle Seahawks have four of the league's best players at their respective positions. Quarterback Russell Wilson was named to his fourth Pro Bowl, tight end Jimmy Graham to his fifth, linebacker Bobby Wagner to his fourth and free safety Earl Thomas to his sixth.

The fact that none of those players is a recent draft pick by the Seahawks is a more sobering reminder of something else: Seattle badly needs an infusion of blue-chip youth into a roster from which the best players are nearing or past the age of 30.

Graham was acquired in a 2015 trade and is 31 years old, while Wilson (2012), Wagner (2012) and Thomas (2010) were drafted at least five years ago. Seattle has had a string of lean drafts since 2013, nothing at all like those that brought them the core of a roster that made it to consecutive Super Bowls following the 2013 and 2014 seasons.

Seattle's past five drafts have yielded two Pro Bowlers. Center Justin Britt (drafted in 2014) made it as an alternate last season, and wide receiver Tyler Lockett (drafted in 2015) was voted in as a kick returner in his rookie season. That means the Seahawks haven't drafted a Pro Bowl position player since 2012.

That's far from the only reason the Seahawks are on the verge of missing the playoffs for the first time since 2011, but it's certainly among the rationale.

It should be noted that several factors contribute to the success or failure of draft picks. It's not as though they're necessarily destined to be stars, busts or something in between. Coaching and development play a role. Luck does, as well. So it wouldn't be fair to chalk up the Seahawks' recent draft misses to the team suddenly losing its keen eye for talent, though it is interesting that the diminishing draft returns have partly coincided with Scot McCloughan's departure. McCloughan, known as one of the NFL's best talent evaluators, left the team just before the 2014 draft.

Whatever the reasons, the results haven't been there. Consider that after the Seahawks waived offensive lineman Mark Glowinski over the weekend, only five of the 28 players that they drafted from 2013 to 2015 remain with the team. There's tight end Luke Willson, Britt, wide receiver Paul Richardson, Lockett and defensive end Frank Clark.

By comparison, the drafts of 2010, 2011 and 2012 -- the first three under general manager John Schneider and coach Pete Carroll -- produced six Pro Bowlers who are still with the Seahawks: Thomas, strong safety Kam Chancellor, cornerback Richard Sherman, linebacker K.J. Wright, Wagner and Wilson.

So the Seahawks have more Pro Bowlers remaining from their first three drafts under Schneider and Carroll than they have players of any kind remaining from the next three drafts.

It takes more than two years for any definitive assessment of a draft class, but the early returns on Seattle's past two have been mixed.

Cornerback Shaquill Griffin and defensive linemen Jarran Reed and Nazair Jones look like mainstays. Running back Chris Carson showed tremendous potential before he got hurt, while another running back, C.J. Prosise, can't stay healthy. The jury is still out on highly drafted offensive linemen Germain Ifedi and Ethan Pocic, while another, Rees Odhiambo, struggled badly when pressed into the starting lineup this season.

The team's top pick this year, defensive lineman Malik McDowell, hasn't played a down because of a head injury, and there's no guarantee that he'll play again.

Running back Alex Collins has been arguably the most productive of the 21 players Seattle drafted over the past two seasons. Unfortunately, he has been productive in Baltimore, since Seattle waived him before the season.

Working against the Seahawks as they attempt to find more difference-makers in the upcoming draft is that they parted with significant 2018 draft capital in recent trades for Sheldon Richardson and Duane Brown. The Seahawks are without picks in the second and third rounds and have seven in all, two of which are in the seventh round. They might get an extra seventh-rounder back, depending on the terms of their conditional trade for offensive lineman Isaiah Battle before the season, but they aren't expected to receive any compensatory picks.

That would seem to increase the likelihood of the Seahawks again trading back in the first round or out of the first round entirely to add more selections. If the Seahawks miss the playoffs this season, that could carry added appeal, since their draft selection would have more trade value.

However many draft selections the Seahawks end up with, they'll need to do more with them than what they've managed to do in recent drafts.