TAMPA -- The Rays added left-handers Ian Seymour and Joe Rock to their 40-man roster on Monday, protecting two of their top pitching prospects from the upcoming Rule 5 Draft.

Seymour is the Rays¡¯ No. 17 prospect and Rock is No. 22, according to MLB Pipeline. Both pitched for Triple-A Durham this past season, putting them in position to contribute for the Rays as soon as next season.

• Which prospects are getting roster spots?

To clear a spot on their 40-man roster, the Rays designated for assignment infielder Austin Shenton. The club also announced it agreed to a Major League contract for 2025 with right-hander Cole Sulser, who was eligible for salary arbitration. Sulser¡¯s split contract is worth $900,000 in the Majors and a guaranteed $450,000 in the Minors.

The deadline for teams to protect eligible players from the Rule 5 Draft is Tuesday at 6 p.m. ET. The Rays took care of their business a day early by selecting the only two eligible prospects on MLB Pipeline¡¯s Top 30 list. The Rule 5 Draft will take place on Dec. 11 during the MLB Winter Meetings in Dallas.

Seymour, 25, was named the Rays¡¯ Minor League Pitcher of the Year after posting a 2.35 ERA and a 0.95 WHIP with 162 strikeouts in 145 1/3 innings over 27 starts for Double-A Montgomery and Durham.

Seymour led Rays Minor Leaguers in ERA, innings, strikeouts and WHIP, and his ERA was the 10th-lowest among all full-season Minor League pitchers. Seymour¡¯s five-pitch arsenal is headlined by a low-90s fastball and a plus changeup that helped him hold opponents to a .187 average while walking only 7.1% of the batters he faced.

• Here are the best recent Rule 5 Draft picks

A second-round pick by the Rays out of Virginia Tech in the 2020 MLB Draft, Seymour didn¡¯t make his professional debut until July 2021 due to flexor soreness. He dominated the rest of that season, recording a 1.95 ERA with 87 strikeouts in 55 1/3 innings over 14 outings. His ascent was stalled in 2022, when he underwent Tommy John surgery, but he returned to the mound in ¡¯23 and returned to form this year.

¡°Ian had a really, really fine season. I think No. 1 is the amount of innings he was able to post this year coming off of injury,¡± assistant general manager Kevin Ibach said in September. ¡°You never know how that's going to work out, if a guy's going to have a setback because of previous injuries. But I think we saw a little bit of a glimpse of what we saw with Ian prior to the injury -- and then some.

¡°The fastball-changeup combo is what is really notable about him. ¡­ In games that he doesn't even have his best stuff, self-admittedly, he'll go out there and be able to find a way to get you through six or seven innings and get people out.¡±

The Rays acquired Rock, 24, from the Rockies last March, trading away 2019 first-round pick Greg Jones. The 6-foot-6 Rock, who throws three pitches with a funky delivery, posted a 4.58 ERA and a 1.40 WHIP with 132 strikeouts in 139 2/3 innings over 27 outings (23 starts) for Durham. Rock finished the season with his best start, striking out 10 while allowing only four hits and a walk over seven scoreless innings against Memphis.

Shenton, 26, cracked the Rays¡¯ Opening Day roster due to a series of Spring Training injuries to key left-handed hitters but played sparingly. The left-handed-hitting corner infielder had a slash line of .214/.340/.405 with a home run in 50 plate appearances over 19 games. But he has thrived in Triple-A, slashing .276/.391/.541 in 144 games at that level from 2023-24.

Sulser made his Major League debut for the Rays in September 2019 and made his way back in a late-July deal with the Mets. The 34-year-old pitched 11 2/3 scoreless innings in six appearances for Tampa Bay, striking out eight and walking six. He posted a 1.66 ERA over 33 appearances in Triple-A this past season.