By Bruce Levine–

NASHVILLE, Tenn. (CBS) — Not willing to sit back on 97 regular-season wins and a successful postseason, the Cubs have begun to press the pedal to the metal for 2016.

On Tuesday at the Winter Meetings, management set in motion a couple of moves that will make the team much stronger and more versatile than last season’s squad. Cubs president of baseball operations Theo Epstein and general manager Jed Hoyer still have payroll flexibility to add more pieces as well after signing super-utility man Ben Zobrist to a four-year, $56-million deal and trading infielder Starlin Castro to the Yankees for right-hander Adam Warren.

“This was a multiple-bank shot,” Epstein said. “We needed all the components of both deals to line up. That included the medicals and timing to sync up. We were not counting any chickens before they had hatched.”

In trading Castro, the Cubs said goodbye to their longest-tenured position player, who made his debut on May 6, 2010 and was one of the last links to the players supplied by the Jim Hendry’s regime. Hendry ran the club from 2002-’11. Castro  was a three-time All-Star shortstop before losing his spot to rookie Addison Russell this past August. The 25-year-old Dominican player became a force for the team in September. He hit a major-league high .419 in the month to supply much of the team’s offense going down the stretch as he manned second base.

The exit of Castro opens the second base job for 23-year-old Javier Baez and the multi-talented Zobrist. Both players can and will play multiple positions next season. The trade and signing leaves the door open for more additions, including a possible big free-agent acquisition like outfielder Jason Heyward or outfielder Alex Gordon.

“We will continue to pursue smaller moves,” Epstein said. “Obviously, we would welcome an impact move if it’s out there.”

The Cubs appear to have somewhere around $17 million to $20 million left in payroll flexibility.

“Really, all the moves we were pursuing previously are still potentially alive for us,” Epstein said. “I would not say we have limited ourselves in any trade talks going forward. We don’t have to act out of need or desperation now. We now can be pretty selective.”

Castro was sorry to leave the Cubs, after playing on his first plus-.500 team of his major league career in 2015.

“I did talk to him,” Epstein said. “I thanked him for his contributions. We wish him well, and I told him I would always be a fan of his. The Yankees really wanted him and had everyday at-bats for him there. He handled it professionally with a little bit of sadness. That was to be expected, leaving his original organization. I have no doubt he will handle this the right way.”

Castro, who will play at age 26 next season, is a .281 lifetime hitter. Castro has more hits than any middle infielder in baseball since 2010. Zobrist, who will turn 35 in May, has a career .355 on-base percentage.

That gives manager Joe Maddon the options to play him at five different positions and lead him off in the lineup if he wishes to. Warren can be used as a starter of relief pitcher. Warren was 7-7 with a 3.29 ERA in 17 starts or the Bronx bombers in 2015. He can start of pitch out of the bullpen.

Bruce Levine covers the Cubs and White Sox for 670 The Score and CBSChicago.com. Follow him on Twitter @MLBBruceLevine.