Ted S. Warren/Associated Press

The five players set to be selected at the top of the 2018 NBA draft appear to be determined. 

With a clear difference between the best prospects and the rest of the bunch, the June 21 event should see Deandre Ayton, Luka Doncic, Jaren Jackson Jr., Marvin Bagley III and Mohamed Bamba go in some order in the top five. 

While each of the elite prospects is impressive, there are some concerns about a few characteristics, which means only one or two of them can be considered as safe picks. 

The safest prospects of the group are the big men who will fill immediate needs on draft day and contend for Rookie of the Year from the first game of the season. 

2018 1st-Round NBA Mock Draft

1. Phoenix Suns: Deandre Ayton, C, Arizona

2. Sacramento Kings: Luka Doncic, SG/SF, Slovenia

3. Atlanta Hawks: Mohamed Bamba, C, Texas

4. Memphis Grizzlies: Jaren Jackson Jr., PF. Michigan State

5. Dallas Mavericks: Marvin Bagley III, PF, Duke

6. Orlando Magic: Trae Young, PG, Oklahoma

7. Chicago Bulls: Wendell Carter, PF/C, Duke

8. Cleveland Cavaliers (from Brooklyn): Collin Sexton, PG, Alabama

9. New York Knicks: Michael Porter, SF, Missouri

10. Philadelphia 76ers (from Los Angeles Lakers): Mikal Bridges, SG/SF, Villanova

11. Charlotte Hornets: Miles Bridges, SF/PF, Michigan State

12. Los Angeles Clippers (from Detroit): Kevin Knox, SF/PF, Kentucky

13. Los Angeles Clippers: Robert Williams, PF/C, Texas A&M

14. Denver Nuggets: Lonnie Walker, SG, Miami

15. Washington Wizards: Shai Gilgeous-Alexander, PG, Kentucky

16. Phoenix Suns (from Miami): Troy Brown, SG, Oregon

17. Milwaukee Bucks: Zhaire Smith, SG, Texas Tech

18. San Antonio Spurs: Keita Bates-Diop, SF, Ohio State

19. Atlanta Hawks (from Minnesota): Dzanan Musa, SF, Bosnia and Herzegovina

20. Minnesota Timberwolves (from Oklahoma City): Mitchell Robinson, C, United States

21. Utah Jazz: Aaron Holiday, PG, UCLA

22. Chicago Bulls (from New Orleans): Chandler Hutchison, SF, Boise State

23. Indiana Pacers: Donte DiVincenzo, SG, Villanova

24. Portland Trailblazers: Jacob Evans, SF, Cincinnati

25. Los Angeles Lakers (from Cleveland): Kevin Huerter, SG, Maryland

26. Philadelphia 76ers: Khyri Thomas, SG, Creighton

27. Boston Celtics: Josh Okogie, SG, Georgia Tech

28. Golden State Warriors: Jalen Brunson, PG, Villanova

29. Brooklyn Nets (from Toronto): Anfernee Simons, SG/PG, Unattached

30. Atlanta Hawks (from Houston): Grayson Allen, SG, Duke

Safest Prospects

Deandre Ayton

Ayton is one of the best frontcourt prospects in recent NBA draft history, as his dominance down low could change the fortunes of a franchise.

The center out of Arizona averaged 20.1 points and 11.6 rebounds per game in his lone collegiate season with Sean Miller's Wildcats.

Ayton has been in the conversation for the No. 1 pick for quite some time, and he believes he's the answer for the Phoenix Suns, per the team's official Twitter account: 

While some players have trouble adjusting to the college level, Ayton shone immediately, as he recorded five straight double-doubles to open his lone season at Arizona.

Ayton totaled 24 double-doubles, and he turned in a pair of dominant 32-point performances at the Pac-12 tournament to seal a trophy for the Wildcats.

The only concern surrounding Ayton is the way he played in the NCAA men's basketball tournament first-round loss against Buffalo, in which he only scored 14 points in a 21-point defeat to the 13th-seeded Bulls.

With the Suns in need of a dominant paint presence to round out their collection of young talent, Ayton seems like the easy selection at No. 1 on June 21.

Mohamed Bamba

After Ayton goes to the Suns at No. 1, there could be some discussion about who the Sacramento Kings take at No. 2. 

Although Luka Doncic is an intriguing prospect, the Kings should take a serious look at Bamba, who like Ayton is a game-changing frontcourt player.

Bamba wasn't a prolific scorer like Ayton, as he averaged 12.9 points per game for the Longhorns, but he ended up in double digits in rebounds per game with 10.5.

The 7-footer's presence alone should alter opponents' game plans, as he will challenge almost every shot that comes his way.

Sue Ogrocki/Associated Press

Bamba is one of the safest options in the draft because of his size and ability around the rim, which could result a double-double average in his rookie season.

Some teams may question Doncic's ability to convert his game to the NBA from the Euroleague, while there are concerns about Bagley's defense.

When it comes to deciding between Bamba and Jackson, teams may go for Bamba's size over Jackson's ability to score in the frontcourt.

Bamba might not go No. 2 to the Kings since they are in need of a scorer like Doncic, but don't be surprised if they take a serious look at the Texas big man before passing him up to the Atlanta Hawks, Memphis Grizzlies and Dallas Mavericks.

Follow Joe on Twitter, @JTansey90.