When Allen was struggling recently, including a 1-5-0 stretch from Dec. 30-Jan. 31, Mason wrote a letter of encouragement to Allen.

HAZELWOOD, Mo. -- Jake Allen has experienced a turnaround lately, and the St. Louis Blues goalie likes to think that 5-year-old Mason Gilbert is a big reason why.

It read:

Dear Jake Allen, you are my favorite player. I hope you win tonight. I know you can do it. You're a great goalie. Love, Mason. I'm five years old.

Mason's dad, Scott, posted the letter on Twitter on Jan. 31, and not only did Allen see it, he's played exceptionally well since, going 4-1-0.

On Monday, Allen invited his No. 1 fan to practice.

"He sent me a message there and I reached out to his dad and I asked for his address and got something in the mail for him," Allen said on Monday. "... That's what it's all about. Any time you can make a kid's day, it's a no-brainer. It doesn't matter what the situation is, when it is, where it is. As soon as I saw him this morning, it put a smile on my face and a smile on his. I'm glad I got to speak to him after."

Tweet from @StLouisBlues: Mason's letter of encouragement to @34jallen worked and today, he got to meet his favorite player in person! #stlblues pic.twitter.com/NQ2gYxSPmR

Mason was wearing a replica of the No. 34 jersey Allen wore at the 2017 NHL Bridgestone Winter Classic. His mother, Robyn, brought Mason to practice, where Allen flipped him a puck, signed a goalie stick and his jersey, and took a picture with him.

The two were able to chat inside the locker room at the Blues practice facility.

Allen showed him his white mask with the three Blues logos, a Canadian flag, his dog's initials and his grandfather's initials, then gave it to Mason to hold.

The two talked about the Winter Classic, which Mason attended, and the conversation turned to Allen's teammate Vladimir Tarasenko.

Allen asked Mason if he thought Allen could stop Tarasenko's shot.

"I don't know," Mason said, drawing laughter.

"You don't think so? Come on, I thought I was your favorite player," Allen said to Mason. "I can stop him, but he's on my team, so I don't have to worry about it. Right?"

Allen's on-ice struggles began Dec. 30 when he was pulled during a 4-0 loss to the Nashville Predators. After getting a win in the Winter Classic against the Chicago Blackhawks on Jan. 2, Allen lost four straight decisions, getting pulled in three of them. He lost to the Winnipeg Jets on Jan. 31, the same day Mason's dad put the letter on Twitter.

During his 1-5-0 stretch from Dec. 30-Jan. 31, Allen allowed 21 goals on 127 shots, an .835 save percentage. Starting with a win against the Toronto Maple Leafs on Feb. 2, Allen is 4-1-0, allowing seven goals on 149 shots, a .953 save percentage.

On Monday, he was named the NHL Second Star for the week ending Feb. 12 after he went 3-0-0 with a 1.00 goals-against average and .967 save percentage.

Allen arranged for Mason to come to a Blues game soon and will give him a tour of their locker room at Scottrade Center.

"It's pretty cool," Allen said. "It shows probably what kind of parents he has, what kind of family he's brought up in. It's really impressive and I think that's really important.

"I believed in myself. I'm glad he was on my side."