Facing a real lineup with something to play for, John Lackey last night provided the strongest evidence yet that his return remains on target.

With Puerto Rico in town to prepare for the World Baseball Classic, Lackey faced a lineup with big league regulars Angel Pagan, Alex Rios, Carlos Beltran, Yadier Molina and old friend Mike Aviles. Lackey was up to the challenge, authoring his strongest start of the spring by throwing three shutout innings, allowing two hits and striking out two in the Red Sox’ 4-3 win.

“It was definitely an upgrade in competition from the last one, a lot of big leaguers, a lot of guys who will be starting in the league,” Lackey said. “Yeah, it was fun.”

Scouts behind home plate had Lackey’s fastball clocked at 90-92 mph, a slight tick up from the 88-90 he featured in his first two starts. He also threw his cutter for the first time as he continues trying to regain the feel for his secondary offerings.

“I definitely felt like it was pretty free and easy tonight, getting up there a little bit better, but I’ve still got a long way to go and it should get better,” Lackey said. “I’m definitely still building arm strength as far as fastball velocity.”

Lackey threw 31 of his 45 pitches for strikes and was able to elevate fastballs without leaving them in the zone. He is returning from 2011 Tommy John surgery and can see the progress he is making.

“It’s a lot more fun when things don’t hurt, you’ve got less things to worry about, for sure,” he said. “You just worry about executing pitches. You don’t worry if this is going to hurt, or things like that. And when you have some success, that’s always more fun than not.”

There’s also one thing Lackey never lost, even during his months of rehabilitation — his competitiveness.

“I think I was born with that,” he said. “That’s not going anywhere.”