Whether one, both or neither of the two precocious pitchers is with Detroit when it opens the season April 6 in Toronto, it appears inevitable that both will be with the Tigers long before the All-Star break and could have significant roles before the season ends.

One of the big differences between Verlander/Zumaya in 2006 and Porcello/Perry in 2009, aside from the foundation of the club, is the question of experience.

Verlander was a former college pitcher who made two cameo starts in 2005. Zumaya had more than three seasons of minor league experience (mostly as a starter) after being drafted out of high school.

Porcello was a high school pitcher in 2007, and his pro experience consists of 125 innings last year, when he won the earned run average title in the high Class A Florida State League.

Perry, a product of Arizona's solid college program, has less than 15 innings of pro experience.

But what both have in common is uncommon ability, poise and the ability to get hitters out.

Porcello is showing that his curve and changeup need refinement, but he also has shown he knows how to keep runners off home plate. Leyland seems more comfortable with the idea of having Porcello avoid on-the-job training in the majors, but he might run out of alternatives.

Right-hander Jeremy Bonderman is healthy after his two in-season surgeries to remove a blood clot and restore circulation to his right shoulder, but his fastball is sick.

Bonderman could open the season on the disabled list unless he gets back into the low 90s by the end of the month.

Left-hander Nate Robertson has taken the lead in the race for the last spot in the rotation, but he's no sure thing -- and now he has a thumb injury.

Left-hander Dontrelle Willis might have walked himself out of more chances, and Leyland has more or less consigned right-hander Zach Miner to the bullpen. (Might he wind up working the last four innings of Porcello's starts?)

A mish-mash of starters last year overworked Detroit's bullpen, and after closer Todd Jones' career ended when his right shoulder broke down in August, the Tigers' season collapsed with it.

Right-hander Brandon Lyon was brought in to compete with right-hander Fernando Rodney to close games for Leyland, but the rest of the bullpen remains in flux.

Miner lost a bid to join the rotation and returned to the bullpen, and retread right-hander Juan Rincon went through the first three weeks of exhibition games unscored upon to apparently make the team.

Left-hander Bobby Seay apparently will be the only southpaw in the bullpen.

More injury problems for Zumaya, plagued by health concerns the last two seasons, made it likely he would remain behind on the disabled list when Detroit broke camp, opening the way for Perry and his high-velocity stuff to make the roster. Perry has closer's stuff but won't be used in that role this year.

Verlander made some adjustments to his mechanics and seemed by mid-March to be back to the form that made him a 17-game winner in 2006 and an 18-game winner in 2007. He lost 17 games last year, and a return to dominance by Verlander is a must if the Tigers are to be an AL Central contender.

Right-hander Edwin Jackson has quietly put up a lot of scoreless innings in the spring and looks as if he'll be a stabilizing force on the staff.

Right-hander Armando Galarraga, a surprising 13-game winner as a rookie, should be able to take a regular turn.

Helping the staff by shoring up the defense, particularly the left side, was an offseason goal of general manager Dave Dombrowski, and spring results seemed to indicate he was successful.

The decision was made last September to return Brandon Inge to third base, where his defense is spectacular, and a shortstop with extreme range, veteran Adam Everett, was signed as a free agent to replace Edgar Renteria, whose range was unsatisfactory in his only season with the Tigers.

Everett suffered an ankle sprain on March 25, but it was not believed to be serious. Ramon Santiago will give him regular rest anyway.

Taking Inge out from behind the plate and dumping catcher Ivan Rodriquez at the trade deadline meant Dombrowski entered the winter in the market for a new catcher, and he obtained Gerald Laird from Texas.

Free agent catcher Matt Treanor was signed to back up Laird and permit the club to send catcher Dusty Ryan out to sharpen his skills.

Carlos Guillen went from first, to third, to left, back to third and then to the bench in September to rest a bad back. The left field experiment lasted only two games, but Detroit is confident Guillen can handle yet another transition. He was signed as an outfielder but moved to the infield in his first pro season.

Having first baseman Miguel Cabrera settled at his new position should let him continue to improve. He has good hands and solid infield skills.

Detroit should have enough offense to compete, if not excel, but next year will have to begin to seriously address getting younger in the field.

Right fielder Magglio Ordonez, though a skilled hitter, is in his mid-30s, as are Guillen and second baseman Placido Polanco. Inge recently turned 30, Everett will never see his 20s again and designated hitter Gary Sheffield is 40.

The presence of Cabrera will let the club turn over its roster with complementary players instead of forcing it to go in search of a big thumper.

There are few position players in the minors of any note, but Detroit hopes shortstop Cale Iorg is one of them -- and that he'll be ready some time in 2010.

Jeff Larish should surface for good at some point in 2009, if not at the beginning of the season. He is the kind of power left-handed bat the club is lacking at the moment.

Larish can play first base, third base and the corner outfield spots without a great deal of embarrassment. The fact he can be optioned to the minors and the other bench candidates cannot will work against him until a deal is made.

As it usually does, though, the season will come down to how well Detroit's starters can do their job. Whether they can turn a lead over to the bullpen and whether the relievers can close the deal is another question.

THE TIGERS WILL CONTEND IF ...: Justin Verlander returns to form, Jeremy Bonderman returns to health with a solid fastball, Edwin Jackson makes another step forward, Armando Galarraga continues his rookie showing and a solid fifth starter emerges. The bullpen also must protect leads the way it did in the World Series year of 2006 and not fritter them away like 2008. If designated hitter Gary Sheffield doesn't show some productivity in the first two months, look for Detroit to replace him with a more versatile player. Should Rick Porcello and Ryan Perry not open the season with the Tigers, they'll be up quickly -- and quite possibly make significant contributions. Pitching is pivotal for the Tigers.

PRIMED FOR A BIG SEASON: RHP Edwin Jackson, squeezed out of Tampa Bay's rotation, was acquired by Detroit to be a reliable starter and could turn out to be much more than that. Jackson went from five victories for Tampa Bay in 2007 to 14 last season, increased his innings from 161 to 183 1/3 and cut his walks to 77 from 88 the year before. This is the first spring where Jackson didn't have to wonder whether he was going to make the team or not, and his confidence in his considerable ability is showing. Big innings, especially the first, have been one of his problems in the past, and he's working to overcome that.

ON THE DECLINE: LHP Dontrelle Willis has gone from 22-game winner for Florida in 2005 to 24 major league innings for Detroit in 2008. He walked 35 batters in those 24 innings and this spring has been only marginally better as he struggles to throw strikes. In his first 8 2/3 spring innings, Willis allowed 17 hits with seven walks for an ERA of 12.46. The Tigers are faced with the prospect of trying to salvage something, or they'll have to release a player they are committed to paying $22 million over the next two seasons.