The deadline especially was beneficial for the Stanford Cardinal. Going into the deadline day, the Cardinal was at risk of returning just one weekend starter with Brett Mooneyham already signed, and Mark Appel still on the board as the Pirates' eighth overall pick.
Appel, though, raised plenty of eyebrows around country, both in the professional and collegiate ranks, when he turned down the Pirates to return to Stanford for his senior campaign.
That decision certainly shook up Pittsburgh. Meanwhile, it gave the Cardinal a sense of much warranted ecstasy.
Also hugely important on deadline day were the decisions by both Georgia Tech outfielder Brandon Thomas and right-handed pitcher Buck Farmer to return to college. Thomas is an athletic outfielder who had a banner junior season, while Farmer is a for-sure preseason All-American going into the 2013 season.
We begin our draft review with a look at the 10 most important returning collegiate players.
RHP Mark Appel, Stanford
Draft review: It wasn't a huge surprise that Appel didn't sign with the Pirates. Often thought to potentially be the top pick in the MLB draft, Appel slid to the No. 8 spot to the Pittsburgh Pirates because of signability concerns. Turns out, that hunch by teams picking ahead of the Pirates was right. Appel always fit the mold of someone that easily could return to college for his senior season.
The skinny: The Cardinal would've been in a precarious situation with their starting rotation entering the 2013 season had Appel joined Brett Mooneyham and signed in the MLB draft. As it stands, though, Appel is back for another campaign, and that gives him even more time to refine his secondary stuff. Appel went 10-2 with a 2.56 ERA in 123 innings of work last season. He also struck out 130 and walked 30, while teams batted .213 against him. Appel is the nation's top returning pitcher.
RHP Buck Farmer, Georgia Tech
Draft review: There was a point during the 2012 season when it looked like Farmer would easily be a top three or four-round pick in the draft. However, much to the surprise of everyone, he dropped to the Brewers in the 15th round. To no surprise at all, he decided to return to college for another season with the Yellow Jackets.
The skinny: Farmer's return to the Jackets is absolutely huge for a team looking to compete for a College World Series appearance. Farmer has a very solid fastball that sits in the low-to-mid 90s, and he's expected to be even better as a senior in 2013. Farmer was 8-4 with a 3.54 ERA in 106 2/3 innings of work last season. He also struck out 115 and walked 37, while teams hit him at a .248 clip.
OF Brandon Thomas, Georgia Tech
Draft review: Have to admit, this one was a surprise. Though Thomas told sources close to Georgia Tech for a couple of weeks before the signing deadline he was headed back to college for another season, this one was rather hard to believe. Still, in the end, the Pirates fourth-round selection stayed true to that talk. His return is huge for the Jackets.
The skinny: Thomas is an outstanding athlete who had a very good 2012 campaign, hence the surprise in his returning to college for another season. Thomas is coming off a rather impressive junior campaign for the Jackets, where he blossomed as a key offensive cog. He batted .360 with 15 doubles, five triples, five homers and 44 RBIs. He also slugged .550 and had a fantastic .481 OBP. His return, along with Kyle Wren, a 30th-round pick to the Reds, is especially huge for Danny Hall's program.
OF Ryan Tella, Auburn
Draft review: Though he went a little under the radar last season because of Auburn's struggles at times on the diamond, Tella is an athletic and talented outfielder drafted in the 11th round by the Giants. It was somewhat of a surprise to see him return to college, but huge for the Tigers. One AU staffer had three exclamation points in a text message to announce Tella's return. Yeah, it's that big.
The skinny: To say Tella's return to Auburn is a big piece of news is an understatement. The Tigers are thrilled to have him back and he provides them with a premier bat to build an offense around entering the 2013 campaign. Tella batted .360 with 12 doubles, four triples, five homers and 34 RBIs last season. He also had a .448 OBP and walked 35 times.
LHP Jerad Grundy, Kentucky
Draft review: After finishing the 2012 season on such a high note, it was a little surprising to see Grundy slide to the Twins in the 27th round. The talented left-handed pitcher had been up to 90-91 in the SEC tournament in May, and showed good stuff during that time. The Twins' loss is a big-time gain for the Wildcats, though.
The skinny: Grundy's return to Kentucky for the 2013 campaign means the Wildcats will have a very solid foundation when it comes to their weekend rotation. The Wildcats lost Taylor Rogers to the draft, but now welcome back Grundy, and junior left-hander Corey Littrell. That gives UK one of the nation's better one-two punches. Grundy went 6-3 with a 3.78 ERA in 85 2/3 innings of work last season. He also struck out 63 and walked 36, while teams hit him at a .245 clip.
OF Tanner Mathis, Mississippi
Draft review: It shouldn't be such a surprise that Mathis returned to Ole Miss considering his commitment to the program and the fact he was a 27th-round pick to the Astros. Still, his return is absolutely huge for an Ole Miss team with the cogs to make a strong run to Omaha next season.
The skinny: Anytime you watched Ole Miss last season, it seemed like Mathis always was the energetic guy getting the offense kick-started. Fortunately for the Rebels, that tradition will continue with his return to Oxford. Mathis is an electric and passionate player, and happens to be the club's top returning hitter after batting .359 with 12 doubles and 23 RBIs last season. He also had a .460 OBP, walked 39 times and struck out on 18 occasions.
OF Raph Rhymes, Louisiana State
Draft review: There was plenty of talk in the scouting community that Rhymes could end up a top-10 round pick, but when the dust settled, he dropped all the way to the Yankees in the 30th round. Rhymes will be a man on a mission next season as he looks to build off a fantastic 2012 season.
The skinny: With the Tigers losing a couple of key cogs entering 2013, Rhymes' return to the lineup is huge. The talented outfielder had a terrific go at it this past season. He was one of the nation's elite hitters the entire season, though, struggled a bit in the NCAA postseason. He batted .431 with 11 doubles, four homers and 53 RBIs. He also had a .489 OBP, walked 22 times and struck out on 13 occasions.
LHP Tyler Joyner, East Carolina
Draft review: As a very high quality left-handed pitcher with success against elite competition, it was a little surprising to see Joyner drop to the Royals in the 35th round. However, what was the Royals' loss is a very important gain for the rebuilding Pirates.
The skinny: East Carolina had a mixed bag of results in its annual fight against the MLB draft. The Pirates lost Kevin Brandt to graduation, while fellow starting pitcher Jharel Cotton signed near the deadline as a 20th-round pick to the Angels. Joyner's return gives the Pirates a solid arm to build a foundation from when it comes to the weekend rotation. The lefty went 6-2 with a 3.01 ERA in 92 2/3 innings last season. He also struck out 68 and walked 12, while teams hit him at a .247 clip.
LHP Sean Hagan, St. John's
Draft review: After losing talented starting pitchers Kyle Hansen and Matt Carasiti to the draft, it became evident the Johnnies needed to hold on to Hagan, a key piece to their weekend rotation last season. Well, Hagan, a 29th-round pick to the Twins, decided to head back to college for his senior season.
The skinny: With the departures of Hansen and Carasiti, the return of Hagan is integral to St. John's ability to compete at an elite level in 2013. Hagan had arguably the strongest campaign of any of the three starting pitchers this past season. He went 8-3 with a 2.90 ERA in 108 2/3 innings of work. He struck out 68 and walked 30, while teams hit him at a .233 clip.
2B LJ Mazzilli, Connecticut
Draft review: Mazzilli's return to the Huskies was one of the huge surprises stemming from the signing deadline. It was fully expected that Mazzilli would sign with the Twins, who selected him in the ninth round. Instead, the veteran second baseman chose to return to Storrs, Conn., for another season.
The skinny: Getting Mazzilli back in the fold is huge for the Huskies, both from a leadership and production standpoint. The veteran led the team in hitting last season, batting .339 with 19 doubles, two triples, nine homers and 38 RBIs. He also had a .404 OBP, swiped 16 bases and struck out 30 times, as opposed to 22 walks. He, as with many players on this list, gives his program a strong foundation to build from.