WEST PALM BEACH, Fla. -- Astros manager Joe Espada has promised since he was hired to improve the team’s fundamentals. That includes tightening up things defensively, holding runners better to reduce stolen bases and being more aggressive on the basepaths to try to take an extra 90 feet when the opportunity presents itself.

Last year, the Astros ranked last in the Major Leagues in extra bases taken percentage, which is the percentage of times the runner advanced more than one base on a single or more than two bases on a double. They also ranked third-last in “runner runs,” which is a Statcast metric designed to use data to evaluate the performance of baserunners in taking extra bases.

“There’s opportunities where I thought last year we could have taken an extra base and someone would have an at-bat where he had an opportunity to drive somebody in with a ground ball to second base,” Espada said. “Great teams do that. We have done that in years past.”

Under the tutelage of third-base coach Gary Pettis and first-base coach Dave Clark, the Astros began baserunning drills Thursday morning on the back fields of CACTI Park of the Palm Beaches. Pettis and Clark worked with players on getting better secondary leads off first base, but the overall message is to be a bit more aggressive.

“We’re trying to put some pressure and take extra bases,” Espada said. “Once our guys feel like we could push ourselves leg-wise and get built up to do stuff like that, I want that to be part of our personality as a team. That’s what we’ve done in the past. I want us to set the tone from the very beginning.”

The addition to Clark -- who returned to the Astros’ coaching staff after serving as the third-base coach for the club from 2009-13 -- was made partially to help improve Houston’s baserunning. Espada said Clark’s extensive experience as a Major League coach and a Minor League manager will be invaluable. In addition to Houston, he has spent time on big league staffs with Pittsburgh (2001-02) and Detroit (2014-20) and managed the Astros' Double-A affiliate in Corpus Christi from 2005-07 and Triple-A Round Rock in '08.

“He’s really going to push some of our guys,” Espada said. “He’s going to give guys some stuff to think about. He’ll remind them, ‘Hey, the right fielder backed up two or three steps after that pitch,’ or, ‘He moved in with two strikes.’ He’s got all that information. He’s always watching. His experience is so valuable, so that’s why I think Dave is going to play a big impact on my baserunning.”

While talking with the players on Thursday, Clark said the message was that the Astros can be more aggressive by taking calculated risks. They want players to run with the bases without fear. Clark said players tend to sometimes be tense when they get on base.

“Our thing is to try to eliminate fear and help guys be comfortable with their leads, be comfortable with their reads and be comfortable with their jumps, and being aggressive on the bases,” he said. “If you make the defense play faster than they normally play, they’re apt to make more mistakes, and if that’s the case we have to take advantage of those mistakes.”

Some of that aggression will stem from knowing what’s going on with the opposition -- who has the weakest arm in the outfield -- and some of it will come from who’s on deck for the Astros. It may make sense to be more conservative with slugger Yordan Alvarez on deck but more aggressive when the bottom of the order is on deck or if there are two outs.

“Our guys are smart about, ‘When is the right time to do it?’” Espada said. “I want us to take some calculated risks. I think it’s important for us to take and put your guys in position to get some easy RBIs. Our guys would rather hit with a man on third base with one out than a man on second base with one out.”