CHESTNUT HILL — The list of FBS quarterbacks who threw for 2,000 yards and rushed for 1,000 last season is just two players long.

One was Jayden Daniels, the LSU sensation who won the Heisman Trophy before becoming the No. 2 overall pick in the 2024 NFL Draft.

The other? Boston College’s diminutive dynamo, Thomas Castellanos.

Listed at just 5-foot-9, 196 pounds, Castellanos was an electric playmaker in his first season with the Eagles — albeit a limited one. His 1,113 rushing yards in 13 games ranked third in the ACC and second among QBs nationwide. No FBS signal-caller scored more rushing touchdowns than his 13.

“The play’s never over with him,” center Drew Kendall said. “He’s a magician with the ball.”

But while Daniels was both a dangerous ball-carrier and the pilot of one of college football’s most prolific passing attacks, Castellanos’ results through the air were decidedly mixed.

He threw 14 interceptions — tied for fourth-most in the nation — with half of those coming in BC’s final four games. He was 78th among qualified FBS QBs in yards per attempt and 88th in completion percentage. His passing efficiency (college football’s version of passer rating) ranked 89th.

There were bright spots, like Castellanos’ 305 passing yards in a near-upset of Florida State and his 265 and three touchdowns with no picks against Louisville. But there were also games like BC’s grind-it-out win over Army, during which Castellanos went a sevice-academy-esque 4-for-9 passing for 44 yards with an INT but rushed 31 times for 142 yards and four scores.

The Eagles’ Fenway Bowl victory over SMU featured a similar Castellanos stat line: 11 of 18, 102 yards, one interception; 21 carries, 156 yards, two touchdowns.

Overall, BC boasted the nation’s 13th-ranked ground game but averaged just 24.8 points per game — good for 80th in the nation. That, plus a similarly suspect defense, resulted in a 7-6 finish followed by a coaching change.

But as the start of the 2024 season approaches, there’s newfound optimism around the Eagles’ aerial potential. The program is hoping the arrival of new head coach Bill O’Brien, coupled with an influx of pass-catching talent and a more favorable ramp-up period for Castellanos, will yield an offense that’s both more productive and less one-dimensional.

At the center of that effort is O’Brien, whose list of prior QB pupils includes Tom Brady, Deshaun Watson and Bryce Young. Since his arrival in early February, the former Patriots play-caller and his staff have worked to improve every aspect of Castellanos’ pass-game toolbox, from pocket presence to reading defenses to knowing when to take the checkdown and when to tuck it and run.

“It’s been really great,” Castellanos said. “I’ve just been a sponge soaking up all the wisdom that he’s passing on in film, and just on and off the field, it’s been really great for me. He has a lot of experience with not just quarterbacks but the game of ball, so me learning from him is going to be great for me.”

The coaches are encouraged by the results thus far. O’Brien called Castellanos “one of the most improved players on our team.” Offensive coordinator Will Lawing said the 20-year-old has “come a long way” since spring ball.

“He’s really bought in to what we want to do, how we want to do it,” O’Brien said. “… It’s been really good.”

The stronger supporting cast around Castellanos has helped. In addition to returning top receiver Lewis Bond and running back Kye Robichaux, BC has several newcomers who look poised to be major contributors on offense.

Wide receivers Jayden McGowan and Jerand Bradley, running back Treshaun Ward and tight end Kamari Morales all arrived from Power Four schools via the transfer portal, and wideout Reed Harris has turned heads this summer after redshirting in 2023.

Bradley and Harris both are 6-foot-5, giving Castellanos a couple of big-bodied playmakers.

“It’s going to help a lot,” the junior QB said of Bradley, formerly of Texas Tech. “I was missing a guy like that last year, having a big body to stretch the field and give an opportunity to have some explosive plays. So it’ll be great having him out there.”

On Harris, Castellanos said his on-field chemistry with the Montana native already rivals his bond with Bond, who caught 53 passes for 646 yards and seven TDs last season.

“He’s one of my go-to guys, and I trust him a lot,” Castellanos said. “He’s a great, big, reliable player. … I can trust him to be where he needs to be at all times.”

Along with his stronger stable of weapons, Castellanos should simply be more prepared for this season than he was a year ago. He transferred to BC from UCF after the Eagles’ spring game last April and opened the season as the backup. After leapfrogging Emmett Morehead partway through the season opener, Castellanos let his instincts and high-end athleticism shape his game.

“He had just got here last year, so it took him a while to get adjusted to the passing game,” Bond explained. “He was just doing what was natural for him. So now this year, with a whole offseason focused on passing, I feel like we’re going to be a way better passing team.”

Despite all of those improvements, Castellanos still will need to overcome his own physical limitations as a 5-foot-9 quarterback — the shortest in the ACC by several inches. Every other starter in the conference is at least 6 feet, and most are 6-2 or taller.

So is Castellanos’ backup, Grayson James, a talented but raw 6-foot-3 transfer from Florida International. James impressed in this year’s spring game and had several standout moments in last week’s intrasquad scrimmage (though those were offset by a pair of ugly interceptions into double coverage).

James could push for playing time if the Eagles’ offense sputters early. But Castellanos enters the season as the locked-in starter and the face of a new era of BC football.

“They definitely compete, but Castellanos is the starter,” O’Brien said. “He’s going to help us win a lot of games.”