Minnesota Twins righthander Samuel Deduno could be set for a short lay-off after doctors confirmed that he has biceps tendinitis which will affect his ability to pitch.

The 30-year-old Dominican complained of a sore shoulder after the recent game against the Chicago White Sox but fans betting MLB World Series are hoping it is only a minor injury that has been caused by the strain of pitching for six months.

Deduno has had a tough campaign since taking part in the World Baseball Classic in March.

Assistant general manager Rob Antony said: “Any time a pitcher comes to you, you have to take that seriously and follow up on it.

“Sometimes, two days later they throw and say, ‘It doesn’t feel like it did. I think I’m OK’. However, there is a chance Deduno will have to go on the disabled list.

“Maybe he’s got a little arm fatigue. It’s not uncommon this time of year for a pitcher to throw through that.”

Deduno is 7-7 with a 3.82 ERA this year, but he has fallen away of late, giving up 13 earned runs in 16⅔ innings in his past three starts, a 7.02 ERA.

According to MLB betting pundits, Twins manager, Ron Gardenhire, has admitted that he thought Deduno's curveball had become less effective of late, saying: "It's getting to a certain point and just hanging there right now. And when his arm speed is good, it's snapping pretty good."

Deduno was signed as an undrafted free agent by the Colorado Rockies in 2003 and went on to play for the San Diego Padres before joining the Twins in November 2011.

Meanwhile, rookie Kyle Gibson failed to impress in the 6-1 defeat to the New York Mets when he gave up ten hits and got just 11 outs.

Gibson has been optioned to the Class AAA Red Wings after his disappointing display.