The first signing period under baseball's new draft restrictions ended with touted pitcher Mark Appel spurning Pittsburgh to remain at Stanford and with 10 teams exceeding their bonus pools but none by enough to forfeit future selections.

Appel was the only unsigned player among 31 first-round picks, turning down an offer of $3.8 million from the Pirates. Appel was projected by some to be the No. 1 selection last month, but several teams shied away from the right-hander because of the expected demands of his adviser, Scott Boras. Appel was selected eighth.

That slot was assigned $2.9 million from the drafting team's bonus pool in baseball's new labor contract, which imposes penalties on clubs that exceed their threshold — the total of the slots for a team's selections in the first 10 rounds. The first pick was slotted for $7.2 million and Houston chose shortstop Carlos Correa, who agreed to $4.8 million.

Pittsburgh was prepared to go as much as 5 percent above its threshold and incur the first level of penalty, a 75 percent tax on the overage. But the Pirates didn't want to fall into higher levels, which include the loss of future draft picks.

"After much thought, prayer and analysis of both opportunities, I came to the conclusion the best decision is to remain at Stanford continuing my studies, finishing my degree and doing all I can to assist the Cardinal baseball team in our goal to win a national championship," Appel said in a statement. "I greatly valued the prospect of a professional opportunity, and I will pursue a professional baseball career after getting my Stanford degree."

Every team that went over stayed within 5 percent of its threshold, according to calculations by Major League Baseball: Boston, the Chicago Cubs, Houston, Kansas City, the Los Angeles Dodgers, St. Louis, San Francisco, Seattle, Toronto and Washington.

"We have shattered the productivity of many teams by putting an artificial cap on their decision-making," Boras said. "It's horrible for baseball and illustrates a real failure in the system."

A team going over by more than 5 percent but less than 10 percent would face a 100 percent tax on the overage and the loss of their next first-round draft pick. Penalties escalate to a 100 percent tax and the loss of a team's next first- and second-round picks (10-15 percent over) and a 100 percent tax and the loss of a team's next two first-round selections (in excess of 15 percent).

Five first-round picks reached agreements on the final day: LSU right-hander Kevin Gausman with Baltimore ($4.32 million for the fourth pick), Oklahoma State left-hander Andrew Heaney with Miami ($2.6 million for ninth), high school right-hander Lucas Giolito with Washington ($2,925,000 for 16th), Clemson third baseman Richie Shaffer, with Tampa Bay ($1.71 million for 25th) and high school right-hander Ty Hensley with the Yankees ($1.2 million for 30th).

Only six first-round picks signed for more than slot: Gausman, Giolito and Shaffer, along with Chicago Cubs outfielder Albert Almora ($3.9 million for sixth), Los Angeles Dodgers shortstop Corey Seager ($2.35 million for 18th) and Boston shortstop Deven Marrero ($2.05 million for 24th). Ten first-round selections signed exactly at slot and 14 signed below.

Just nine players among the 338 taken in the first 10 rounds failed to sign. Among them was Connecticut second baseman L.J. Mazzilli, the son of former major league player and manager Lee Mazzilli. Selected by Minnesota in the ninth round, Mazzilli will return to the Huskies for his senior season.

The signing deadline didn't apply to Florida outfielder Preston Tucker because he is a college senior, and Houston has until June to sign the seventh-round pick.

Because Appel failed to sign, Pittsburgh will get an extra pick in the first round next year, the ninth selection overall. The Mets will get an extra selection after the 11th pick of the second round for not signing high school righty Teddy Stankiewicz and Oakland will get an additional pick after the third round for failing to sign high school lefty Kyle Twomey.

Appel, who turns 21 on Sunday, also failed to sign in 2009, when Detroit selected him in the 15th round with the 450th pick after his final season with Monte Vista High in San Ramon, Calif. Appel will go back into next year's draft.

Under the labor deal, agreed to in November, the deadline for draft picks to sign was 5 p.m. Friday, a month earlier than he rules in the previous collective bargaining agreement. The change led to fewer picks waiting until the final hours to sign.

Trying to end a record streak of 19 consecutive losing seasons, the resurgent Pirates are tied with the Cincinnati Reds for the NL Central lead.

"We drafted Mark Appel to sign Mark Appel. We were excited about the opportunity to add him to a plethora of quality, young arms," Pirates general manager Neal Huntington said during a telephone conference call. "It didn't happen. So now we turn the corner. This, too, shall pass. We move forward."

Because Appel didn't sign, the Pirates will receive an extra first-round pick in next June's draft, the ninth selection overall. The Pirates also could gain an extra selection from baseball's first competitive balance draft, which will be held Wednesday in Secaucus, N.J.

"We may be looking at three of the top 45 picks in the country," Huntington said. "Some have argued next year's draft class is going to be better than this year's draft class."

Boras also represented prior first-round picks Pedro Alvarez and Gerrit Cole in their negotiations with the Pirates.

"Selecting Mark was a calculated risk, as we knew he would be a difficult sign," Huntington said. "As an organization, we need to continue to take these types of calculated risks. While we would've preferred to add Mark to the group of talented prospects in our system, we wish Mark, and his family, nothing but success in the future."