SEATTLE - Edgar Martinez has always been as much a part of Safeco Field as the retractable roof. Fans enter the main gates off Edgar Martinez Drive. They enjoy games while eating in Edgar's Cantina beyond left field. And they cheer whenever his 1995 division series-winning double is replayed on the video board.

More important, Martinez has played a key role in giving Mariners something else to applaud: Seattle's offensive improvement.

The Mariners averaged 3.38 runs per game last season before Martinez took over as hitting coach June 20. After that, they averaged 4.53 runs the rest of the season. After finishing 12th or lower in the American League in runs scored the past eight seasons, Seattle is currently seventh in the AL. The Mariners are third in home runs and fourth in OPS.

"I would say he's helped big time," Robinson Cano said. "The way he talks to us. He's patient. He tells you positive things. ... No matter how good you are, you always need that person who will tell you and remind you, 'Don't forget, you used to do this, you used to do that. You're better doing this.' So it is good to have people like that."

Cano in particular had a terrible start in 2015, hitting just .245 with two home runs and a .621 OPS before Martinez took over. He hit .317 with 19 home runs and an .892 OPS afterward. While stomach issues played a role in the first-half slump, Cano also was swinging at a higher percentage of pitches out of the strike zone and trying to pull the ball a lot more. He says Martinez played a major role in getting him back on track.

"I knew how to play through it, but he helped me a lot," Cano said. "He reminded of things, like, 'Don't forget who you are,' and helped me out with things that I don't want to tell people because you don't want them to know your secrets, but he was really good."

Martinez always has been good. Actually, great. A two-time batting champ, Martinez hit .312 for his career with a .418 OBP and a .933 OPS. Asked once whether he feared any batter more than Edgar, then-Twins manager Tom Kelly replied, "Who else would there be?"

He was so good that the annual award for the best designated hitter was named after him following his retirement in 2004.

He served as a spring training instructor with Seattle for several years before becoming a roving minor league instructor at the start of 2015. When offered the major league job last summer, he wasn't sure he wanted the full-time gig. Then he figured, "My wife is working full time. My kids are in school. So I'm spending a lot of time by myself. So I thought I would do it, and it's been fine."

Make that very fine. Thanks to their improved hitting, the Mariners are in first place this late in the season for the first time since 2003.

After a stellar career between the lines for the Mariners, Edgar Martinez now keeps close tabs on the M's as Seattle's hitting coach. Jennifer Buchanan-USA TODAY Sports

"He does a great job of teaching us and giving us insight and giving us as much information as we want or need," outfielder Seth Smith said. "He's the one who talks about our swing, helps us prepare, scouts the opposing pitchers. He brings a calm, confident demeanor to the offensive side of the ball that we feed off."

There is often talk that the best players do not always become the best coaches because they do not fully understand the challenges facing players of lesser talent. Mariners instructor and former catcher Dan Wilson, who played 11 years with Martinez, says that is not the case with his old teammate.

"As a player, he was very, very thorough and very particular, and all those things are great qualities to have as a coach," Wilson said. "His approach, the way he looks at this, the way he dissects, have got be helpful.

"Even though he was a gifted hitter, he was a guy who really broke down his swing, really understood his swing, really understood hitting in general. I think that's the difference with a guy like that."

Patient, detailed and communicative, Martinez also emphasizes that hitters have a plan about what they are going to do at the plate. He holds a meeting with the batters at the start of each series and goes over the starting pitcher before each game.

This sort of attention to detail went beyond hitting for Martinez. Because he has the eye disorder strabismus, he would perform eye exercises before games to keep his vision and depth perception as good as possible. He would even weigh his bats on a postal scale before games. Those routines play a role as a hitting coach as well.

"Sometimes I throw out the question, 'Do you know how heavy this bat is? I know it says 31 ounces, but is it really 31?"' Martinez said, adding that he also wants players to know if they are left-eye or right-eye dominant. "There are right-handed hitters who are right-eye dominant, and if they open up their stance a little bit, they can benefit a little bit."

Ken Griffey Jr. complained about Safeco's dimensions before the ballpark was even completed, and many other hitters have complained about it as well. But Martinez never let it get to him, hitting roughly as well there as he did on the road. He doesn't want Seattle's hitters to let it get to them either.

"We don't talk about the ballpark," Martinez said. "We don't mention anything that is negative. We have a plan and an approach, it's going to be fine. We focus on what we want to accomplish."

And so far, they are giving their fans reason to cheer alongside Edgar Martinez Drive.