Stanford ace right-hander Mark Appel began the spring of 2012 with a chance to be a top-10 pick, perhaps even No. 1 overall. There were a number of clubs that graded him the best player available. For reasons beyond the talent on the field, Appel fell to No. 8, failed to sign with the Pittsburgh Pirates and went back to Palo Alto for his senior season.

It was a bit of a risk, particularly with high attrition rate for pitching prospects, not to mention the loss of negotiating leverage since he cannot make the identical decision this season, having now exhausted all of his college eligibility.

With the Cardinal failing to qualify for NCAA regionals, Appel's college career has come to a close, and it appears the move to return will pay off once he's taken off the board next Thursday, as he's expected to be a top-three pick. Scouts tend to agree he made the right choice to return to school, with a caveat.

"He was dynamite most of the year," one National League club's regional crosschecker said. "He was very good (last year), but definitely better this season."

A national crosschecker tabbed Appel the most polished power pitcher he's scouted in 10 years, with only one exception: Stephen Strasburg, the No. 1 pick in the 2009 draft.

"There were at least a handful of starts where I just said to myself, 'he can help us right now,'" said the crosschecker. "And Strasburg is the only other time I have said that in the last decade."

Each talent evaluator agreed Appel helped himself, if anything, in terms of where he'll be selected and the bonus money he's likely to successfully command, and he's matured on the mound, preparing him for what may be a quicker ascent to the big leagues.

"If injuries weren't part of the equation," the national checker explained, "pitchers might take this route more. (There was) more consistency in everything he did, he had his best stuff more and he worked through his delivery like a pro."

The one caveat, as promised, is the general belief that the sooner one starts their professional career the better, as pro instruction is the best most careful coaching one can receive.

"I do wonder where he'd be if he'd signed last July and got a handful of starts under his belt and gone through spring training," the regional crosschecker said. "Might he be in Double-A, dealing and dominating, pushing for a big league call-up as early as this summer?"

There's always a chance the 6-foot-5, 215-pound right-hander may have been better off starting his pro career 10 months ago, but now that he's through the spring healthy, it's difficult to argue with the results. He will almost certainly earn him more bonus money than the $3.8 million bonus he was reportedly offered by the Pirates, and perhaps the experience during his senior season ends up more important to his career than anything else.

Appel finished the season at 10-4 with a 2.12 ERA and 130 strikeouts in 106 1/3 innings over 14 starts. He walked just 23 batters, allowed just 80 hits, two home runs, and went the distance on four occasions.

With the draft regulations dictating the value of each selection, the Houston Astros may tab a player other than Appel with the top pick next week. If that occurs, it won't be due to anything Appel did or didn't do on the mound. He sharpened his command, worked out some inconsistencies in his delivery, showed better control and command and his off-speed stuff was better.

Although Stanford is out, there are still plenty of top prospects taking part in regionals this weekend, which you can watch on WatchESPN. Here is what to watch for.

North Carolina third baseman Colin Moran, who is all but certain to come off the board in the top 10 picks next Thursday, joins left-hander Kent Emmanuel (2.11 ERA, 110 2/3 IP, 92 H, 79 SO, 22 BB) and their Tar Heels teammates in hosting a regional and will open play versus Canisius Friday. Emmanuel, considered a Day 2 talent by most, is slated to go Saturday versus an opponent to be determined by Friday's results.

Moran enters the regional batting .357/.485/.579 with 13 home runs and a 55-20 strikeout-to-walk ratio, and Keith Law has him going No. 1 overall in his latest mock draft.

Ole Miss ace Bobby Wahl (1.99 ERA, 90 2/3 IP, 61 H, 76 SO, 42 BB) and 2014 top prospect Carlos Rodon, a left-hander at North Carolina State with 151 strikeouts in 101 innings, highlight the region's talents. If both schools win or lose, they'll see each Saturday with the potential for the two arms to go toe-to-toe.

Wahl is generally considered a second-round pick.

In terms of draft prospects and potential matchups, this may be the most interesting region with New Mexico third baseman D.J. Peterson, Cal State Fullerton OF/RHP Michael Lorenzen and Arizona State right-hander Trevor Williams all squaring off against one another.

Williams has struggled a bit the second half of the season, so any strong starts for him moving forward could get him back into the conversation for the top-50 picks, though it may be too late for that. Peterson is getting top-15 buzz and Lorenzen, a two-way talent, figures to come off the board between picks 40 and 80, unless he cuts a deal with a club to go earlier than that.

• San Diego third baseman Kris Bryant (.340/.500/.860, 31 HR, 62 BB, 40 SO) will compete in the Los Angeles Regional that includes Cal Poly, UCLA and San Diego State. A potential second-round matchup against the Bruins could pit Bryant versus right-hander Adam Plutko, a Day 2 talent, but one who flashes mid-rotation stuff, sometimes better.

• Oklahoma right-hander Jonathan Gray (1.55 ERA, 110 IP, 69 H, 21 BB, 127 SO), among the small handful of possibilities for the Houston Astros at No. 1 overall, will pitch in the Blacksburg Regional, hosted by Virginia Tech. If the matchup occurs, Gray could be a nice challenge for Hokies third baseman Chad Pinder (.327/.409/.489), who started the year with a chance to improve his stock into the top 40 or 50, but didn't have the big year.

• Right-handers Ryan Eades (2.69 ERA, 93 2/3 IP, 94 H, 75 SO, 27 BB) of LSU and Ryne Stanek (1.40 ERA, 90 IP, 70 H, 76 SO, 35 BB) of Arkansas have at least one more start this season, with Eades staying home in the Baton Rouge Regional and likely going Saturday. Stanek and his Razorbacks are in the Manhattan Regional.

Eades is attempting to solidify his stock as a potential first-round pick -- which is far from a lock, and may not even be probable at this stage -- while Stanek looks to wow clubs into a top-10 selection or better.

• Mississippi State right fielder Hunter Renfroe (.352/.445/.652) remains home in the Starkville Regional, where he'll get a shot at a couple of smaller schools in Central Arkansas (Friday) and either South Alabama or Mercer Saturday.