The big influx of rookies over the last several seasons has since changed the landscape of Major League Baseball. The aging veterans have become more like dinosaurs on the verge of extinction, while a youth rebellion has taken over the big leagues. Names like Corey Seager, Tyler Naquin, Michael Fulmer and Gary Sanchez were some of this year’s big breakouts.

Who’s on tap for 2017? Let’s take a look at five first baseman who could contribute as early as Opening Day.

Keep in mind, this is a list of the top first base prospects ready to contribute at the big league level in 2017. It is not a ranking of the best overall first base prospects, which is why you won’t find names like Josh Naylor and Bobby Bradley, who are both a year, or more likely two, away.

You also won’t find Josh Bell on this list because he ended the season starting at both first and right field for the Pirates. He was every bit the prospect we thought he was, hitting for nice average, some pop and walking more than he struck out, so throw out the numbers declaring that he didn’t “officially” have enough at bats to make him a rookie this season; Bell is the Pirates first baseman.

Nor will you find Cody Bellinger. Despite Bellinger being an absolute stud, Adrian Gonzalez can still hit and is under team control through 2018. That’s not to say Bellinger won’t get a chance next season, but if he does, it will be in the outfield, removing him from eligibility for this list.

DAN VOGELBACH, SEATTLE MARINERS

Big Dan is one of the more fun prospects to watch smack a home run — doing his best Kyle Schwarber impersonation — but the sad truth was as much as Cubs fans loved him, he wasn’t going to fit in Chicago. Part of that was due to Anthony Rizzo, and some of that may be due to the fact that he could be better suited as a designated hitter. That’s why the late-July trade to the Mariners should see Vogelbach on the Opening Day big league roster.

The 23-year-old left-handed hitter did reach the big leagues after spending a month with the Triple-A Tacoma Rainiers. He split his time evenly, playing four games at first and four games at DH. He didn’t do anything memorable at the plate, but he also has little left to prove in the minor leagues. Incumbent first baseman Adam Lind is a free agent and 34-year-old “rookie” Dae-ho Lee was nice, but not much more. The first base job could be Vogelbach’s for the taking behind a strong spring.

CASEY GILLASPIE, TAMPA BAY RAYS

Gillaspie hits for average and has 20-home run power, with fantastic plate discipline. That already makes him one of the Rays best hitters entering 2017.

The main concern surrounding Gillaspie was how complete his game could be. Everyone knew he had power when he was drafted 20th overall in 2014 out of Wichita State, but they questioned his defense and hit ability. After a hand injury forced him to miss a bulk of 2015, concerns about his power suddenly arose.

He put all those concerns behind him with a career-year in 2016. He shined for the Durham Bulls in his Triple-A debut as he slashed .307/.389/.520 with seven home runs and 13 doubles. While that may have been enhanced by a .358 BABIP, it’s still safe to assume that Gillaspie could very well be a .280 hitter with 20+ home run power, especially with his 2016 117-to-80 strikeout-to-walk ratio, showing that he has patience at the plate.

His play at first was nearly flawless in Durham as well, committing just one error in 407 total chances and posting a range factor over nine. While Brad Miller’s bat broke out in a big way for the Rays in 2016, he has experience at multiple positions. If the Rays feel Gillaspie is deserving of a shot on Opening Day with a big spring, they can shift Miller and make room for Gillaspie.

Find out who else made the list by heading on over to Today’s Knuckleball for my full feature by clicking on the link below: