Boston Red Sox Hagadone reported to the
Lowell Spinners of the Low-A
New York–Penn League after signing his first professional contract with the
Boston Red Sox on July 1, . He set a franchise record by twirling 23 consecutive scoreless innings to finish the season, breaking
Matt Kinney's mark of 18 innings in . He was roughed up in his pro debut, allowing five runs on six hits and a walk while fanning one over one and one third innings against the
Aberdeen IronBirds on July 18. He said this about his pro debut: Hagadone held opposing hitters to a .103 average and just one extra-base hit, a double, during his scoreless streak for the rest of 2007. He struck out at least one batter in each of his 10 starts and averaged 12.2 punchouts per 9 innings. His 1.85 ERA led all Spinners hurlers with at least 20 innings pitched. In , Hagadone made three starts in his first full pro season at Single-A
Greenville Drive of the
South Atlantic League before being placed on the disabled list on April 19 and missing the rest of the season as the result of
Tommy John surgery. He did not allow an earned run in 10 innings of work with the Drive, fanning 12 and allowing only five hits and three unearned runs. He gave up two unearned runs in his first inning of the season on April 5 against the
Kannapolis Intimidators, snapping a personal 23-inning scoreless streak. He made his last start on April 16 against the
Greensboro Grasshoppers, leaving the game following two and one third shutout innings. Following the season, Hagadone was ranked by
Baseball America as the Red Sox's number three prospect and the number two pitcher. He was also rated as having the best slider in the system for two straight seasons in 2007 and 2008. He made 7 starts down the stretch, splitting time between the Single-A
Lake County Captains and High-A
Kinston Indians. Hagadone split the 2010 season between Kinston and the Double-A
Akron Aeros. In 29 appearances (17 starts) for the two affiliates, he compiled a 3-5 record and 3.57 ERA with 89 strikeouts across innings pitched. On November 19, 2010, Hagadone was added to the Indians'
40-man roster to protect him from the
Rule 5 draft. Hagadone was called up to the Indians on August 26, 2011. In nine appearances for the Indians during his rookie campaign, Hagadone logged a 1-0 record and 4.09 ERA with 11 strikeouts over 11 innings of work. In a loss versus the
Tampa Bay Rays on July 6, 2012, Hagadone fractured his left forearm in a fit of frustration. The injury required a metal screw to be inserted during surgery and recovery was expected to take 6–8 weeks. Said Indians
manager Manny Acta, "I think Nick learned his lesson. A big part of this game is learning how to control your emotions." Hagadone was subsequently placed on the minor league disqualified list. He made 27 appearances for Cleveland during the 2012 season, struggling to an 6.39 ERA with 26 strikeouts and one
saves across innings pitched. Hagadone made 36 appearances for the Indians during the 2013 campaign, posting an 0-1 record and 5.46 ERA with 30 strikeouts across innings pitched. In 2014, Hagadone finished 1–0 with a 2.70 ERA and 27 strikeouts in innings of relief over 35 games. Hagadone made 36 appearances out of the
bullpen for Cleveland in 2015, recording a 4.28 ERA with 28 strikeouts across innings pitched. Hagadone was
designated for assignment following the acquisition of
Collin Cowgill on December 2, 2015. As that date was also the non-tender deadline that year, and the Indians did not tender him a contract, and Hagadone subsequently became a free agent. On December 18, 2015, Hagadone signed a minor league contract with the
Milwaukee Brewers organization. However, the deal was voided on January 11, 2016, due to "significant issues" that arose in his physical. He did not pitch professionally in 2016.
Seattle Mariners On January 31, 2017, Hagadone signed a minor league contract with the
Seattle Mariners. He made 28 appearances out of the
bullpen for the Triple-A
Tacoma Rainiers, posting a 3-3 record and 3.51 ERA with 35 strikeouts across innings pitched. Hagadone was released by the Mariners organization on July 1. ==Scouting report==