Solomon Thomas is the last remaining unsigned draft pick for the San Francisco 49ers, which hasn't been an issue because the rookie defensive lineman has been unable to join his new teammates during their offseason program. The only practice that he has taken part in was a rookie minicamp held in May following the draft.

The NFL prohibits incoming rookies from joining their new clubs until their school's finals are complete. That isn't an issue for most rookies, but Thomas' college, Stanford, is on the quarter system and finishes later than most universities. That placed his eligibility date into mid-June, which was too late to join any of the 49ers' organized team activities.

This is the second straight year that a 49ers first-round selection has been unable to participate in the majority of the team's offseason program. Last year, guard Joshua Garnett, who also played college football for Stanford, was impacted by the rule despite having already finished all of his classes. While he worked out and studied on his own during the delay and eventually joined his new teammates for a final minicamp in June, Garnett did not begin the 2016 season as a starter.

For Thomas, the delay has not been wasted. He has been using the time to work with some of the NFL's best defensive players – both past and present.

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The Sacramento Bee reported that Thomas was among the many pupils at a "Pass Rush Summit" held by Denver Broncos edge defender Von Miller at Stanford.

Miller, who is renting a Bay Area home for the summer, had numerous NFL defenders in attendance for his pass rush crash course. They included big names like recently retired edge rusher DeMarcus Ware, who played for the Dallas Cowboys and Denver Broncos, and Atlanta Falcons linebacker Vic Beasley, who led the league in sacks last season with 15.5.

Also part of the gathering was Broncos pass rusher Shane Ray, Jacksonville Jaguars defensive end Malik Jackson, and Seattle Seahawks defenders Cliff Avril and Cassius Marsh. That is a lot of potential knowledge for the 49ers rookie to soak up.

"The presence of Seahawks, Falcons and Jaguars players may have been beneficial to Thomas because they have operated the same defense San Francisco will run this year," writes Matt Barrows of the Sacramento Bee.

Strong showing for year 1 at @vonmiller Pass Rush Summit. Thanks to @stanfordfball for the hospitality

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Also in attendance at the summit were 49ers defensive lineman Arik Armstead, who has also been working this offseason at the team's Leo spot which is a position reserved for the team's best pass rusher, and tackle Trent Brown. Brown appears to be the only offensive lineman to have taken part in the event. Brown garnered praise from Miller last offseason when the 49ers and Broncos held joint practices together.

The summit wasn't the first time that Thomas has worked with Ware. He worked out with the former Cowboys and Broncos star in the spring.

"When you get a rookie that's mature to call a veteran and say, 'Can you help me before rookie training camp?' That was big," Ware said earlier this offseason on NFL Network's "Good Morning Football."

Thomas, who was initially given the jersey number 96, has since changed it to 94 in honor of Ware, whom Thomas hopes to emulate during his career.

Miller and Ware aren't the only NFL talents who Thomas has sought out. He recently worked out with Hall of Fame defensive lineman Warren Sapp, who documented it on Instagram. Sapp had an illustrious 13-year career spent with the Tampa Bay Buccaneers and the Oakland Raiders. During that time, he was selected to seven Pro Bowls and won Super Bowl XXXVII with the Buccaneers, on which he was teammates with safety John Lynch, who is now the 49ers' general manager.

Rise and grind! #RushmanWork #FiveStepsToQb @sollythomas90

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Sometimes you have to get close enough to smell it!! #RushmenWork @sollythomas90

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According to the Sacramento Bee, Thomas may even further his NFL education by joining the quartet of 49ers players heading to Hawaii next week to take part in an annual training program led by Seahawks defensive end Michael Bennett. The 49ers defenders already committed to the trip are Armstead, DeForest Buckner, Eli Harold, and Ronald Blair.

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The 10-day program on the North Shore of Oahu focuses on cardio and pass-rushing techniques in order to improve players' overall game and lengthen their careers. Last offseason, the program included about a dozen NFL defensive stars and even more are expected to take part next week.

Thomas became the third defensive lineman the team has selected with its top pick in the past three years. In 2016, the 49ers selected Buckner out of Oregon with the seventh overall selection. The year before, they selected Armstead – also out of Oregon – with the 17th overall selection.

Thomas saw his draft stock rise in 2016 when he had 61 tackles, 8.5 sacks, and was First-Team All PAC-12. That stock rose further following the Sun Bowl against North Carolina and his showing at the NFL Scouting Combine, where he ran a 4.69-second 40-yard dash

The 49ers begin training camp on July 27th and, assuming Thomas is signed by then, the third overall selection should be able to finally rejoin his teammates.