Michael Moise DeMark
- Bats Right, Throws Right
- Height 6' 0", Weight 200 lb.
- School Marietta College
- High School Penn-Trafford High School
Mike DeMark has pitched as high as AAA.
DeMark went to college with plans of playing infield for Marietta College's baseball team. In tryouts, they timed his fastball at 86 mph and told him he would be a pitcher instead; he told his father "I don't want to pitch" but the move proved a good one as he would have a lengthy pro career. He had a 12-2, 1.79 record as a sophomore, fanning 101 in 90 1/3 IP. He was 10-0 with a 3.13 ERA asa junior and 9-1 with a 2.81 ERA as a senior. He saved game one of the 2006 Division III College World Series, won Marietta's second game then closed out the title-clincher. 
Undrafted out of college, he signed with the independent Florence Freedom and was 1-4 with a save and a 3.22 ERA for them in 2006. He tied for 7th in the Frontier League with 41 games pitched. San Diego Padres scout Bill Bryk signed him in January 2007.  He was 2-1 with a 3.74 ERA for the Lake Elsinore Storm that summer, fanning 70 in 53 innings. He split 2008 between the Storm (1-2, 2.17 in 42 G) and San Antonio Missions (0.76 ERA in 12 G), with a WHIP of 1.04 and an ERA of 1.72.
In 2009, the right-hander pitched for San Antonio (2-3, Sv, 3.15 in 57 G) and the Portland Beavers (0 R in 4 IP), reaching AAA three years after no team had wanted to draft him. He tied Brad Brach for third in the Padres chain in games pitched and he tied Bobby Cassevah for third in the Texas League in that department. He was 0-1 with a 7.42 ERA for the Peoria Saguaros in the Arizona Fall League.
DeMark split 2010 between San Antonio (1-0, 0.60 ERA in 12 G) and Portland (4.14 in 30 G) again, this time with the bulk of the work coming at the higher classification. Let go by San Diego, he returned to the independent leagues with the York Revolution, saving one game and posting a 2.61 ERA in 13 outings. The Arizona Diamondbacks signed him and he spent most of the summer excelling for the Mobile BayBears (3-2, 15 Sv, 1.85, 48 K, 9 BB in 34 IP). He also was briefly with the Reno Aces (0 R in 2 IP). He was 5th in the Southern League in saves and third in the Arizona chain.
The Pennsylvanian spent all of 2012 in AAA with Reno, going 5-5 with a 4.19 ERA in 53 games. He tied Jean Machi for 8th in the 2012 PCL in games pitched and tied Eury De La Rosa for second in the D'backs chain in that department. That winter, he had a 4.85 ERA for the Naranjeros de Hermosillo. In the summer of 2013, he pitched in the Oakland A's system but did not fare as well (3-3, 4 Sv, 5.59) for the Midland Rockhounds.
In the independent leagues for a third stint, he split 2014 between the Somerset Patriots (7-2, 2 Sv, 4.38) and York (1 UER in 6 IP). He played in his third different league, allowing two runs in 6 1/3 IP for the Cardenales de Lara in Venezuela, going 0-1. He was superb in limited work for York in 2015 (1-0, 3 Sv, 0.83 ERA in 23 G). He allowed one run in four regular season innings for Lara and had a 8.31 ERA in the postseason, reinforcing other teams. 
DeMark was on the mark for York in 2016 - 0-1, 35 saves, 0.76 ERA, 0.69 WHIP, 62 K in 47 2/3 IP. He broke Rommie Lewis's team records for saves in a season and in a career.  He was named the Atlantic League's All-Star closer.  He was two saves shy of league leader Jon Hunton.
With Lara in 2016-2017, he allowed two runs in eight innings and saved six games to tie Cody Hall for 7th in the Venezuelan Winter League. He was signed by the Uni-President Lions of the Chinese Professional Baseball League in January.  Before the CPBL season got under way, though, DeMark was selected to play for the Italian national team in the 2017 World Baseball Classic (his grandfather was Italian ).
The Classic did not go well for DeMark, though. In the opener, he relieved A.J. Morris with a 7-5 deficit against host Mexico, the bases loaded and two outs. He allowed a two-run single to Sebastián Elizalde then got Sebastián Valle on a fly. It would be the only out he would record in three outings. Tommy Layne took over in the 8th and Italy rallied for a 10-9 upset. In his next outing, he relieved Morris with a 5-5 tie in the 7th against Venezuela. José Altuve hit into an error, then Martin Prado and Miguel Cabrera singled to put Venezuela ahead. Layne relieved and both inherited runners would score; Italy wound up losing, 11-10. In their finale, a win-or-go-home game against Venezuela (which was in the same boat), he was summoned to try to close out the game, with Italy holding a surprising 2-1 lead. Cabrera this time homered off him and Víctor Martínez walked on four pitches. Rougned Odor hit what was originally thought to be a homer; on replay, it was turned into a run-scoring single. Frailyn Florian relieved. Italy lost, 4-3, DeMark taking the defeat. His 108.00 ERA was the highest of anyone who retired a batter; Australia's Jon Kennedy allowed two runs and retired no one.