CHICAGO -- The dad was on his computer, monitoring the MLB Draft online as picks kept rolling in throughout Monday afternoon. His son was in his car, heading home from their mailbox, unaware that an important phone call had arrived.

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The son's phone buzzed and he answered.

"Mason, where are you?'" said the dad. "You need to get home."

They knew the Cubs were on the radar. Area scout Evan Kauffman and vice president of baseball operations Dan Kantrovitz had made a visit to their home in the spring. Later, the Cubs invited Mason to Arizona, where he got a tour of the team's facilities and threw a bullpen session in Chicago's pitch lab.•

The Cubs liked the life in Mason's fastball and were intrigued by an impressive splitter that is rare among the amateur ranks. The kid has an impressive 6-foot-4 frame with room to grow, an easy delivery that projects well for a starting pitcher, and he loves diving into the data and metrics.

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Mason's name was called by Chicago in the eighth round of the MLB Draft.

"He's somebody that we've been following for a while," Kantrovitz said. "This was Mason's moment."

Mason's dad just happens to be Mark McGwire, one of the greatest sluggers in the history of the Major Leagues. He was an icon with the rival Cardinals and was part of the historic 1998 home run chase with Cubs home run king Sammy Sosa.

Life's funny sometimes. Here was Mark McGwire -- once the single-season home run champion with 70 blasts for St. Louis in that magical summer of '98 -- letting out a proud dad laugh about his kid being drafted by the Cubs. Of course it was the Cubs.

After Chicago picked Mason McGwire, his dad received a congratulatory text message from Cardinals president of baseball operations John Mozeliak. Recognizing the amusing element to this situation, Mark McGwire had some fun with his reply.

"I said, 'How ironic is it,'" McGwire said, "'that three or four years from now, Mason might be toeing the hill and making his debut against St. Louis in Wrigley Field?' How great would that be?"

The Cardinals' legend let out a laugh when asked whether he would be wearing a Cubs hat when that moment arrives.

"Absolutely," he said. "I'm looking through the internet trying to buy some Cubs apparel. So, yes, I will be donning Cubs apparel."

Kantrovitz emphasized, however, that this moment was not about the dad.

The fact that Mason's dad was a Rookie of the Year, 12-time All-Star, Home Run Derby champion, World Series champion and has 583 home runs on his 16-year resume is just a "fortuitous" part of all of this. What it does mean, though, is that Mason has been blessed with a great resource and some experience being around big leaguers.

Mason and Jackson Holliday (Matt Holliday's son and selected No. 1 overall) used to play in the outfield during batting practice when Mark McGwire was a coach with St. Louis (2010-12). Mason and Justin Crawford (Carl Crawford's son and the 17th overall pick) hung out during Mark's days coaching with the Dodgers ('13-14).

From the time Mason was around 10 years old, his dad began to see the makings of a pitcher in his son. Max, an older brother of Mason, was more of a hitter. The Cubs were also looking at Max a year ago, but he spent this past season playing for Oklahoma.

"I see myself in both of them," Mark McGwire said. "I see myself as a hitter in Max. I see myself when I was a pitcher in Mason. But, they're so far more advanced than me at that age. That being said, they have so much more to learn."

In his senior season at Capistrano Valley High School (Calif.), Mason McGwire had 46 strikeouts in 32 2/3 innings with a 3.43 ERA. His fastball has been up to 93-94 mph, and his curveball is still developing. It is the splitter that really has the Cubs excited.

"It's turned into what we think is a pretty interesting potential out pitch for him," Kantrovitz said.

During the 2019 season, Mark McGwire was invited to Oakland to be enshrined in the A's Hall of Fame. He brought his kids and Mason met Hall of Famer Rollie Fingers. The kid chatted up the pitching legend and asked him how he threw his splitter.

"He showed me. Since then, I've been throwing it," Mason said. "I've been throwing it for three years now and it's been really good for me."

"I've got a picture of them talking," chimed in the proud dad.

Mark McGwire said he believed having his son enter professional baseball now -- rather than pitching in college -- will give the Cubs the chance to "mold him into a beast." The dad has seen a few pitchers in his day (he took 362 deep in his MLB career) and thinks Mason could find his way up the organizational ladder swiftly.

"It was so cool when Dan called," Mark McGwire said. "I'm like, 'This is the time for Mason to just go.' I would not be shocked to see Mason toeing the mound in Wrigley Field in three or four years at 21 or 22 years old. This is how hungry he is."

Fans will surely enjoy seeing the dad in the stands wearing a Cubs cap.

For the Cubs, that was not what this was about.

"Mason put himself in this position," Kantrovitz said. "The way we look at it, we would've drafted him where we did regardless of the name on the back of his jersey."

And that meant a lot to the son.

"I respect that a lot," Mason McGwire said. "It means they want me for who I am -- not who my dad was. That shows that they care a lot about me. I really like that."