Jimmy Howard will soon graduate at the top of his class.

The 23-year-old goaltender retains his perch atop Red Wings Central’s mid-season prospect ranking, fending off skyrocketing defenseman Jonathan Ericsson, who climbed six spots to No. 2, and third-ranked blueliner Jakub Kindl.

All three play for the Grand Rapids Griffins, and Howard gets the nod at the top because he has taken another a step forward in his development.

“He keeps us in every game — he’s focused, he’s very confident and his physical regime has been a plus in terms of his quickness,” Griffins general manager Bob McNamara said. “At this stage, it appears he is (ready for the NHL).”

Howard, heralded Detroit’s goalie of the future since being drafted in 2003, played in the American Hockey League all-star game and is 16-16-2 with a 2.59 goals-against average, a .913 save percentage and two shutouts. He has become much more consistent and, most importantly, eliminated soft goals.

“He rarely gives one up,” McNamara said. “That’s just part of a goalie’s development. When they’re beating him, they’re beating him with a good goal. He looks just about ready. If he finishes (strong), he will be a factor next year in Detroit.”

Here’s a look at the full mid-season ranking, with each player’s movement relative to the preliminary ranking included in parentheses.

1. G Jimmy Howard (-), Grand Rapids (AHL). See above.

2. D Jonathan Ericsson (+6), Grand Rapids (AHL). The monstrous blueliner’s phenomenal rate of progression isn’t slowing in his second pro year.

3. D Jakub Kindl (-1), Grand Rapids (AHL). It’s been a rocky rookie year for Kindl, but that’s common for young blueliners. He remains a high-end prospect.

4. LW Justin Abdelkader (-1), Michigan State (NCAA). It’d be nice to see him put up more points, but he’s a safe prospect with a bright future.

5. LW Cory Emmerton (-1), Brampton (OHL). All he does is score and he’s smart both ways. Mono kept him from starring at the world junior championship.

6. D Brendan Smith (-1), Wisconsin (NCAA). He’s an offensive blueliner living up to his reputation in college. Now, his defensive game must follow.

7. LW Darren Helm (+3), Grand Rapids (AHL). Speedy, spunky and looking great as an AHL rookie. The Red Wings see him as a full-time NHLer by 2009-10.

8. LW Jan Mursak (-2), Belleville (OHL). He’s been playing better since a mid-season trade, but still isn’t having the huge offensive year many hoped for.

9. LW Dick Axelsson (-2), Djurgarden (Swe). He may be the most skilled player on the list, but he’s extremely thin and still needs to be more consistent.

10. D Kyle Quincey (-1), Grand Rapids (AHL). He’s had a tough season after being demoted, but he can play in the NHL. The question is, when?

11. C Joakim Andersson (+1), Boras (Swe-2). He is a great two-way player who looks like a good bet to crack the top 10 next season.

12. D Logan Pyett (+1), Regina (WHL). The gifted “offenseman” showcased his skills on Canada’s third pairing en route to a gold medal at the world junior.

13. G Daniel Larsson (+4), Djurgarden (Swe). If he’s willing to play in the minors, the Wings should sign him. He recently made his Swedish national-team debut.

14. RW Mattias Ritola (+1), Grand Rapids (AHL). The numbers don’t show it, but he’s got an impressive skill-set. The Red Wings are enamored with his potential.

15. C Ryan Oulahen (-1), Grand Rapids (AHL). He’s another Matt Ellis, an oft-forgotten prospect who wears a letter and gets it done all over the ice.

16. LW Johan Ryno (-5), Djurgarden (Swe). Ryno needs to make sure he doesn’t get lost in the shuffle after leaving the AHL for Sweden.

17. RW Igor Grigorenko (-1), Salavat Yulaev (Rus). It’s been a dismal season for Grigorenko, who was an elite prospect before a 2003 car crash.

18. C Evan McGrath (-), Grand Rapids (AHL). He’s slowly coming around, but still hasn’t translated his massive junior success to the pros.

19. C Zack Torquato (-), Erie (OHL). The Red Wings expected Torquato to score 100 points this year. At his current pace, he’ll finish a long way off.

20. LW Anton Axelsson (-), Timra (Swe). He’s a defensive-minded role player who can shut down opponents, but a shortage of contracts will hurt him.