Miller and Franklin shared reps at the position during infield drills over the first two days of full-squad workouts. Both were drafted as shortstops, with Franklin moving to second on a full-time basis only last year.
"Nick came in, and we had a great talk," McClendon said. "One of the things I told him was, 'Look, we've got a Hall of Fame second baseman, and that's just the way it is. This is a new chapter in your career. One door is closing; another is opening. It's an opportunity for you. I'm going into this with my eyes wide open. You have an opportunity to compete for the shortstop position, and I wish you the best of luck.'
"I said I don't have any preconceived notions, and I mean that. I do not have any preconceived notions of who is going to be my shortstop. He's going to have a great opportunity, and I wished him the best."
McClendon values defense at the shortstop position but would be happy with a solid glove man who contributes offensively as well.
"You've got to be able to catch the ball," he said. "I'm looking for a guy that is going to make all the routine plays. We had a guy in Detroit [Jhonny Peralta] that I called Steady Eddy. He wasn't flashy, but everything that was hit to him, he caught the ball and threw it over there.
"Everybody complained he didn't have the range, but you knew when the ball was hit to him, he was going to get an out. And I think that's important. That's what I'm looking for. I'm not looking for flashy play. I'm looking for a guy that is very sound fundamentally, makes the plays consistently and provides offense."
Miller, 24, hit .265/.318/.418 with eight home runs and 36 RBIs in 306 at-bats last year. Franklin, 22, hit .225/.303/.382 with 12 home runs and 45 RBIs in 369 at-bats. Both have Minor League options remaining and could open the season in Triple-A Tacoma if they do not win the starting job.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.