Jamison Gibson-Park says the competition for scrum-half spots with Ireland will be intense leading into the Six Nations.
Gibson-Park was one of five scrum-halves named in Andy Farrell's first Ireland training squad on Monday, the head coach selecting 45 players for a "24-hour mid-season stocktake" on 22 and 23 December.
New Zealander Gibson-Park qualified for Ireland on residency grounds last summer but knows he faces a battle for the number nine shirt against the likes of Conor Murray and the in-form John Cooney.
"There are nines all around the country who are playing really well at the moment," said Gibson-Park.
"From my point of view it is the most competitive the nine jersey has been in a long time."

Gibson-Park has made seven starts for Leinster this season and while the 27-year-old hasn’t had any contact with Farrell, he hoped his form was good enough to earn a call-up.
"It’s the usual story, put your head down and keep working, hopefully play well for Leinster and see what that leads to," he said.
"It’ll be good. There are a good few lads here who are involved (with Ireland) and it’ll be nice to get into that environment with them."
Having come off the bench in Leinster’s landslide win over Northampton in the Champions Cup, Gibson-Park is set to be restored to the starting line-up for Friday's Pro14 fixture against Ulster.
Leinster have won all 11 matches in all competitions this season but their perfect record will be tested during Christmas fixtures against all three of their provincial rivals.
"This next block of games is very important for us as a team and goes a long way to defining our season," said Gibson-Park.
"Everyone loves to have a crack at Leinster and the inter-pros are a good chance for the other teams to knock us off our perch."