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After an offseason in which the San Francisco 49ers have lost a number of key players both to retirement and to rival teams, it is more important than ever that lesser-known players step up and make an impression in 2015. And a player well-placed to enjoy a breakout year that few people are talking up about is defensive lineman Quinton Dial.

Dial's importance to the 49ers grew on Monday with the announcement that Justin Smith was retiring from the NFL after 14 seasons in the league and seven as the heartbeat of the San Francisco D-line. With his departure, the Niners look young on the defensive side of the trenches. However, they are still extremely talented in that area.

Defensive line coach Scott Brown has a plethora of exciting D-linemen to work with, and at this stage, it is Dial who looks the most promising.

49ers Defensive Line Grades 2014 Run Defense Pass Rush Overall Justin Smith 13.2 2.1 16.6 Ray McDonald 7.8 6.4 15.2 Ian Williams 8.2 4.0 12.9 Quinton Dial 1.2 1.1 3.2 Mike Purcell 0.1 0.2 0.4 Tank Carradine -0.9 -0.2 -0.2 Tony Jerod-Eddie -9.5 -4.6 -13.0 Pro Football Focus

Indeed, Dial—after sitting out pretty much all of his rookie year in 2013 due to injury—produced play in the second half of the 2014 campaign to indicate he could be a force up front for the Niners for years to come. Last season, Dial racked up 30 tackles and two sacks in 14 games and six starts.

According to Pro Football Focus, Dial also recorded 10 quarterback hurries and two hits, earning a final grade of 3.2. Coming on just 329 defensive snaps, those numbers are even more impressive when you consider that Smith had just 10 more hurries on more than double the number of snaps at 715.

Production is not everything when it comes to the 49ers defensive front in their 3-4 system, yet Dial looked comfortable in that defense in 2014 and was also able to display considerable versatility. At 6'5" and 318 pounds, Dial played as a 5-technique defensive end and as a nose tackle, showing the capability to two-gap and also generate interior pressure and earning particular praise from new head coach Jim Tomsula, per David Fucillo of Niners Nation.

And you talk about those two nose guards with Ian [Williams] and [Glenn] Dorsey, I'd dare say to you, when you watched Quinton Dial toward the end of last year, that was a pretty dad-gum good nose guard. I see him more as an end, but he sure does have NFL snaps on game day as a starting nose guard that are really good.

The former Alabama man's proficiency at two positions in the trenches should not be undervalued. And it speaks to the quality of Dial that, per PFF, he had his second-best game against the 49ers' biggest rival in the Seattle Seahawks. Dial graded out at 2.5 for the Week 15 loss at CenturyLink Field, producing two quarterback hurries and two tackles.

One of the qualities Dial demonstrated during that defeat in Seattle was his powerful hands, which he used to good effect to make this play in tackling Christine Michael.

NFL.com

It is tough to see in the mass of bodies near the play, but Dial utilizes his hands superbly on this play to get away from Lemuel Jeanpierre, break back toward the ball-carrier and make the tackle. However, as indicated earlier, Dial showed strength in rushing the passer, which his overtime sack of Drew Brees in the Week 10 win over the New Orleans Saints evidenced.

NFL.com

Here, Dial quickly diagnoses the play-action pass and, due to his quick feet, is able to pursue Brees effectively and get a jump on the opposing offensive lineman, recording a sack that put the Saints in a hole. This came just before another sack and forced fumble that allowed the Niners to kick the winning field goal.

It is tough to get a read on how Dial will pan out this early in his career, yet the signs are promising for a player who looks to possess the power and the mobility to have success on the Niners defensive front. And Smith's retirement has opened a door for Dial despite San Francisco's decision to draft defensive end Arik Armstead in the first round.

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Armstead is seen as Smith's natural successor, but at 21 years old, the former Oregon Duck is still very raw and will likely need to take quick and significant steps in his development to start right away. The most probable scenario is that Glenn Dorsey, missing last year through injury, slides from nose guard to end, with Dial either competing with Ian Williams for the tackle spot or with Darnell Dockett and Tank Carradine for the other end spot.

Tony Jerod-Eddie is also in the mix but has purely been a rotational guy for most of his career. Dockett should serve predominantly as a pass-rusher, meaning it could well be a direct competition with Carradine, who did not even play his first game until Week 10 of last year and seems to be a step behind Dial in his development despite some flashes late in the season.

Even if Dial loses out to Carradine, he can be valuable in rotation as a nose guard, particularly with Williams being prone to injuries early in his career. A movable piece like Dial is always important to a defense, and his presence on the 49ers unit should enable San Francisco to spell the aging Dockett and be more patient with the physical but unpolished freak Armstead.

Dial is not a player who will immediately scream X-factor to most observers. Watching his play in 2014, though, what quickly becomes clear is that he is a guy with the ability to dominate opposing linemen from two different positions and the physical skills to sustain that success over an extended period.

With Smith sailing off into the sunset, the argument can be made that the 49ers defensive line is unproven. It is a school of thought with some credence. However, one man Tomsula evidently trusts is Dial. Expect him to be given the opportunity to prove that trust is well-placed, and expect the former fifth-round pick to rise to it and help fill the void left by a three-time All-Pro.

Nicholas McGee is a San Francisco 49ers Featured Columnist based in Leeds, England. Follow him on Twitter @nicholasmcgee24.