DETROIT -- Former Tigers first-round picks Beau Burrows and Derek Hill will get their long-awaited chance to make an impression in big league camp. More importantly for the club's sake, they won't be plucked by another organization.

The Tigers made a half-dozen additions to their 40-man roster on Wednesday to protect prospects from next month's Rule 5 Draft. Joining Burrows and Hill on the roster are high-rising hitting prospect Isaac Paredes (fifth on MLB Pipeline's Tigers prospect rankings), outfielder Daz Cameron (eighth) and right-handers Kyle Funkhouser (18th) and Anthony Castro (20th).

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The moves bring the Tigers' roster to 39. Teams must have an open roster spot to be eligible to pick in the Rule 5 Draft, where Detroit has the first overall selection. If the Tigers sign a free agent before then, they can still open a spot by dropping a player.

The six players constitute the largest crop of prospects the Tigers have added to their roster since they added seven players in 2017. This year's group, however, was different, a mix of former first-round picks and well-regarded prospects as the stockpile of players the organization has collected under its rebuilding effort begin to reach the upper levels of the farm system. Even with six moves, the Tigers faced difficult decisions on others.

Burrows, the 22nd overall pick in 2015, likely would've been on Detroit's roster already if not for injuries. Once rated as the Tigers' top prospect, the 23-year-old right-hander looked poised at midseason to become the first of the club's high-rated starting prospects to make the Majors. Then came a disastrous 2019 season that stalled with shoulder inflammation and ended early with an oblique strain.

Burrows' numbers in Toledo included a 2-6 record, a 5.51 ERA and 4.4 walks per nine innings. With four pitches, including a mid-90s fastball, and a bulldog mentality, however, he pitches like a top prospect when he's on. He's ranked the Tigers' No. 14 prospect by MLB Pipeline.

Like Burrows, Hill's path up the Tigers system hasn't been smooth, making the Tigers' decision on him difficult. The team left him off the roster when he was Rule 5 eligible last offseason, guessing correctly that he would go unclaimed. A strong, healthy season at Double-A Erie changed the outlook.

Hill, ranked 28th in the system by MLB Pipeline, was a human highlight reel in the SeaWolves' outfield, showing the defensive instincts and athleticism that drew comparisons to Torii Hunter out of high school. Hill's offense remains a work in progress, having batted .243 with a .705 OPS and 147 strikeouts over 120 games with Erie. Still, he held his own with three homers, six RBIs, six steals and a .798 OPS over 17 games in the Arizona Fall League. Hill turns 24 in December and has the potential to be a late bloomer.

By comparison, the decision to add Paredes to the roster was a no-brainer. In an organization starved for young impact hitters, he's the one such prospect who realistically could arrive in Detroit next year. Paredes' .784 OPS at Double-A Erie was strong in a pitcher-friendly Eastern League, where he was one of the youngest players at age 20. His plate discipline belied his age, with nearly as many walks (57) as strikeouts (61) over 127 games to go with 13 home runs.

Cameron, too, was a clear choice, despite a season of growing pains that nearly saw him demoted from Triple-A Toledo. After a strong Spring Training cameo appearance with the Tigers, he batted just .214 in Toledo with a .707 OPS and 152 strikeouts in 448 at-bats, showing the learning curve of someone who jumped from Class A ball to Triple-A the year before. With his 23rd birthday coming in January, Cameron still has time to develop into a Major League center fielder.

Like Burrows, Funkhouser was a strong candidate for a late-season callup before he struggled down the stretch. He had some very good outings in Toledo and Erie, but also had three starts in which he didn't make it out of the first, and another in which he was chased in the second inning with general manager Al Avila watching in person.

Funkhouser's Mud Hens numbers included a 3-7 record, 8.53 ERA, 7.7 walks and 9.2 strikeouts per nine innings across 18 starts.

The Tigers have made two moves this offseason to keep Castro, who was eligible to become a Minor League free agent before the club signed him to a successor contract. Though the 24-year-old Venezuelan didn't generate the attention of top prospects Casey Mize and Matt Manning in Erie, Castro had some of the best pitches on the SeaWolves' staff. Castro shined as a hard-throwing swingman, allowing just 75 hits over 102 1/3 innings with 65 walks and 116 strikeouts before posting a strong Arizona Fall League campaign.

Two ranked Tigers prospects were left off the 40-man roster and will be available in the Rule 5 Draft, though their chances of being selected appear iffy. Right-hander Elvin Rodriguez, ranked 22nd by MLB Pipeline, allowed a .228 average, 1.175 WHIP and 3.0 walks per nine innings at Class A Advanced Lakeland, but the 21-year-old has yet to pitch at Double-A. He joined the Tigers' organization in the Justin Upton trade two years ago.

Outfielder Jacob Robson is more advanced, having spent the last season and a half with Toledo. His .267 average was down 28 points from 2018 to go with 132 strikeouts in 112 games, but his 53 walks allowed him to salvage a .352 on-base percentage and .750 OPS and set up a career-high 25 stolen bases. With Major League rosters expected to expand to 26 players, the Windsor, Ontario, native could fit with another club as an extra outfielder and pinch-runner.